Customized keyword query suggestions on online social networks

ABSTRACT

In one embodiment, a method includes accessing multiple posts of an online social network, each post being associated with a first entity of the online social network. The method also includes generating multiple candidate keywords by extracting one or more n-grams from content of the accessed posts and calculating a rank for each candidate keyword. The method also includes storing one or more candidate keywords in association with the first entity, each stored candidate keyword having a calculated rank higher than a threshold rank and sending, to a second entity of the online social network, one or more suggested queries associated with the first entity for display on the client system, each suggested query comprising one or more of the stored candidate keywords associated with the first entity.

TECHNICAL FIELD

This disclosure generally relates to social graphs and performingsearches for objects within a social-networking environment.

BACKGROUND

A social-networking system, which may include a social-networkingwebsite, may enable its users (such as persons or organizations) tointeract with it and with each other through it. The social-networkingsystem may, with input from a user, create and store in thesocial-networking system a user profile associated with the user. Theuser profile may include demographic information, communication-channelinformation, and information on personal interests of the user. Thesocial-networking system may also, with input from a user, create andstore a record of relationships of the user with other users of thesocial-networking system, as well as provide services (e.g. wall posts,photo-sharing, event organization, messaging, games, or advertisements)to facilitate social interaction between or among users.

The social-networking system may send over one or more networks contentor messages related to its services to a mobile or other computingdevice of a user. A user may also install software applications on amobile or other computing device of the user for accessing a userprofile of the user and other data within the social-networking system.The social-networking system may generate a personalized set of contentobjects to display to a user, such as a newsfeed of aggregated storiesof other users connected to the user.

Social-graph analysis views social relationships in terms of networktheory consisting of nodes and edges. Nodes represent the individualactors within the networks, and edges represent the relationshipsbetween the actors. The resulting graph-based structures are often verycomplex. There can be many types of nodes and many types of edges forconnecting nodes. In its simplest form, a social graph is a map of allof the relevant edges between all the nodes being studied.

SUMMARY OF PARTICULAR EMBODIMENTS

In particular embodiments, a social-networking system may providecustomized keyword query suggestions related to particular entities ofan online social network to a querying user. A user interface associatedwith the social-networking system may comprise fields for displaying oneor more query suggestions associated with each search instance. Insteadof typing in a complete search query into a query field, a user mayconduct a search against the online social network by, for example,clicking on one of the query suggestions. The efficiency of searchingmay be improved if the displayed query suggestions are customized to fitthe user's interests, such that the user's probability of using at leastone of the query suggestions is increased. Query suggestions may begenerated based on keywords extracted from a variety of sources such as,for example, a search history associated with the querying user, contentassociated with the querying user, or a plurality of trending or populartopics on the online social network. Additionally, query suggestions maybe generated based on keywords extracted from content associated withentities other than the querying user. The social-networking system maycustomize its query suggestions to fit the interests of the queryinguser by providing query suggestions associated with one or more entitiesthat the querying user is interested in. For example, a querying user,who is a friend of the user “Xiao” on the online social network, may bevisiting a profile interface associated with Xiao and decide to conducta search from the current profile interface. The social-networkingsystem may then provide a list of suggested queries to the queryinguser, each suggested query incorporating one or more keywords extractedfrom Xiao's posts.

In particular embodiments, the social-networking system may first accessand extract one or more n-grams from posts associated with a firstentity. The first entity may be, for example, a user, a group of users,an organization, a place, a website, or another suitable entityassociated with the online social network. Posts associated with thefirst entity may include data such as, for example, status updates orother textual data, location information, photos, videos, links, music,other suitable data or media, or any combination thereof. Thesocial-networking system may then generate one or more keywords (e.g.,words, phrases, other suitable text strings) based on the extractedn-grams and store the keywords on a server or a client system. Thestored keywords may then be used to generate one or more querysuggestions, which may be provided to a querying user determined to bepotentially interested in the first entity.

The embodiments disclosed above are only examples, and the scope of thisdisclosure is not limited to them. Particular embodiments may includeall, some, or none of the components, elements, features, functions,operations, or steps of the embodiments disclosed above. Embodimentsaccording to the invention are in particular disclosed in the attachedclaims directed to a method, a storage medium, a system and a computerprogram product, wherein any feature mentioned in one claim category,e.g. method, can be claimed in another claim category, e.g. system, aswell. The dependencies or references back in the attached claims arechosen for formal reasons only. However any subject matter resultingfrom a deliberate reference back to any previous claims (in particularmultiple dependencies) can be claimed as well, so that any combinationof claims and the features thereof are disclosed and can be claimedregardless of the dependencies chosen in the attached claims. Thesubject-matter which can be claimed comprises not only the combinationsof features as set out in the attached claims but also any othercombination of features in the claims, wherein each feature mentioned inthe claims can be combined with any other feature or combination ofother features in the claims. Furthermore, any of the embodiments andfeatures described or depicted herein can be claimed in a separate claimand/or in any combination with any embodiment or feature described ordepicted herein or with any of the features of the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example network environment associated with asocial-networking system.

FIG. 2 illustrates an example social graph.

FIG. 3 illustrates an example partitioning for storing objects ofsocial-networking system 160.

FIG. 4 illustrates an example profile interface for displaying keywordquery suggestions.

FIGS. 5A-5B illustrate an example newsfeed interface for displayingkeyword query suggestions.

FIG. 6 illustrates an example method 600 for providing customizedkeyword query suggestions related to particular entities of an onlinesocial network.

FIG. 7 illustrates an example computer system.

DESCRIPTION OF EXAMPLE EMBODIMENTS

System Overview

FIG. 1 illustrates an example network environment 100 associated with asocial-networking system. Network environment 100 includes a clientsystem 130, a social-networking system 160, and a third-party system 170connected to each other by a network 110. Although FIG. 1 illustrates aparticular arrangement of a client system 130, a social-networkingsystem 160, a third-party system 170, and a network 110, this disclosurecontemplates any suitable arrangement of a client system 130, asocial-networking system 160, a third-party system 170, and a network110. As an example and not by way of limitation, two or more of a clientsystem 130, a social-networking system 160, and a third-party system 170may be connected to each other directly, bypassing a network 110. Asanother example, two or more of a client system 130, a social-networkingsystem 160, and a third-party system 170 may be physically or logicallyco-located with each other in whole or in part. Moreover, although FIG.1 illustrates a particular number of client systems 130,social-networking systems 160, third-party systems 170, and networks110, this disclosure contemplates any suitable number of client systems130, social-networking systems 160, third-party systems 170, andnetworks 110. As an example and not by way of limitation, networkenvironment 100 may include multiple client systems 130,social-networking systems 160, third-party systems 170, and networks110.

This disclosure contemplates any suitable network 110. As an example andnot by way of limitation, one or more portions of a network 110 mayinclude an ad hoc network, an intranet, an extranet, a virtual privatenetwork (VPN), a local area network (LAN), a wireless LAN (WLAN), a widearea network (WAN), a wireless WAN (WWAN), a metropolitan area network(MAN), a portion of the Internet, a portion of the Public SwitchedTelephone Network (PSTN), a cellular telephone network, or a combinationof two or more of these. A network 110 may include one or more networks110.

Links 150 may connect a client system 130, a social-networking system160, and a third-party system 170 to a communication network 110 or toeach other. This disclosure contemplates any suitable links 150. Inparticular embodiments, one or more links 150 include one or morewireline (such as for example Digital Subscriber Line (DSL) or Data OverCable Service Interface Specification (DOC SIS)), wireless (such as forexample Wi-Fi or Worldwide Interoperability for Microwave Access(WiMAX)), or optical (such as for example Synchronous Optical Network(SONET) or Synchronous Digital Hierarchy (SDH)) links. In particularembodiments, one or more links 150 each include an ad hoc network, anintranet, an extranet, a VPN, a LAN, a WLAN, a WAN, a WWAN, a MAN, aportion of the Internet, a portion of the PSTN, a cellulartechnology-based network, a satellite communications technology-basednetwork, another link 150, or a combination of two or more such links150. Links 150 need not necessarily be the same throughout a networkenvironment 100. One or more first links 150 may differ in one or morerespects from one or more second links 150.

In particular embodiments, a client system 130 may be an electronicdevice including hardware, software, or embedded logic components or acombination of two or more such components and capable of carrying outthe appropriate functionalities implemented or supported by a clientsystem 130. As an example and not by way of limitation, a client system130 may include a computer system such as a desktop computer, notebookor laptop computer, netbook, a tablet computer, e-book reader, GPSdevice, camera, personal digital assistant (PDA), handheld electronicdevice, cellular telephone, smartphone, other suitable electronicdevice, or any suitable combination thereof. This disclosurecontemplates any suitable client systems 130. A client system 130 mayenable a network user at a client system 130 to access a network 110. Aclient system 130 may enable its user to communicate with other users atother client systems 130.

In particular embodiments, a client system 130 may include a web browser132, such as MICROSOFT INTERNET EXPLORER, GOOGLE CHROME or MOZILLAFIREFOX, and may have one or more add-ons, plug-ins, or otherextensions, such as TOOLBAR or YAHOO TOOLBAR. A user at a client system130 may enter a Uniform Resource Locator (URL) or other addressdirecting a web browser 132 to a particular server (such as server 162,or a server associated with a third-party system 170), and the webbrowser 132 may generate a Hyper Text Transfer Protocol (HTTP) requestand communicate the HTTP request to server. The server may accept theHTTP request and communicate to a client system 130 one or more HyperText Markup Language (HTML) files responsive to the HTTP request. Theclient system 130 may render a web interface (e.g. a webpage) based onthe HTML files from the server for presentation to the user. Thisdisclosure contemplates any suitable source files. As an example and notby way of limitation, a web interface may be rendered from HTML files,Extensible Hyper Text Markup Language (XHTML) files, or ExtensibleMarkup Language (XML) files, according to particular needs. Suchinterfaces may also execute scripts such as, for example and withoutlimitation, those written in JAVASCRIPT, JAVA, MICROSOFT SILVERLIGHT,combinations of markup language and scripts such as AJAX (AsynchronousJAVASCRIPT and XML), and the like. Herein, reference to a web interfaceencompasses one or more corresponding source files (which a browser mayuse to render the web interface) and vice versa, where appropriate.

In particular embodiments, the social-networking system 160 may be anetwork-addressable computing system that can host an online socialnetwork. The social-networking system 160 may generate, store, receive,and send social-networking data, such as, for example, user-profiledata, concept-profile data, social-graph information, or other suitabledata related to the online social network. The social-networking system160 may be accessed by the other components of network environment 100either directly or via a network 110. As an example and not by way oflimitation, a client system 130 may access the social-networking system160 using a web browser 132, or a native application associated with thesocial-networking system 160 (e.g., a mobile social-networkingapplication, a messaging application, another suitable application, orany combination thereof) either directly or via a network 110. Inparticular embodiments, the social-networking system 160 may include oneor more servers 162. Each server 162 may be a unitary server or adistributed server spanning multiple computers or multiple datacenters.Servers 162 may be of various types, such as, for example and withoutlimitation, web server, news server, mail server, message server,advertising server, file server, application server, exchange server,database server, proxy server, another server suitable for performingfunctions or processes described herein, or any combination thereof. Inparticular embodiments, each server 162 may include hardware, software,or embedded logic components or a combination of two or more suchcomponents for carrying out the appropriate functionalities implementedor supported by server 162. In particular embodiments, thesocial-networking system 160 may include one or more data stores 164.Data stores 164 may be used to store various types of information. Inparticular embodiments, the information stored in data stores 164 may beorganized according to specific data structures. In particularembodiments, each data store 164 may be a relational, columnar,correlation, or other suitable database. Although this disclosuredescribes or illustrates particular types of databases, this disclosurecontemplates any suitable types of databases. Particular embodiments mayprovide interfaces that enable a client system 130, a social-networkingsystem 160, or a third-party system 170 to manage, retrieve, modify,add, or delete, the information stored in data store 164.

In particular embodiments, the social-networking system 160 may storeone or more social graphs in one or more data stores 164. In particularembodiments, a social graph may include multiple nodes—which may includemultiple user nodes (each corresponding to a particular user) ormultiple concept nodes (each corresponding to a particular concept)—andmultiple edges connecting the nodes. The social-networking system 160may provide users of the online social network the ability tocommunicate and interact with other users. In particular embodiments,users may join the online social network via the social-networkingsystem 160 and then add connections (e.g., relationships) to a number ofother users of the social-networking system 160 whom they want to beconnected to. Herein, the term “friend” may refer to any other user ofthe social-networking system 160 with whom a user has formed aconnection, association, or relationship via the social-networkingsystem 160.

In particular embodiments, the social-networking system 160 may provideusers with the ability to take actions on various types of items orobjects, supported by the social-networking system 160. As an exampleand not by way of limitation, the items and objects may include groupsor social networks to which users of the social-networking system 160may belong, events or calendar entries in which a user might beinterested, computer-based applications that a user may use,transactions that allow users to buy or sell items via the service,interactions with advertisements that a user may perform, or othersuitable items or objects. A user may interact with anything that iscapable of being represented in the social-networking system 160 or byan external system of a third-party system 170, which is separate fromthe social-networking system 160 and coupled to the social-networkingsystem 160 via a network 110.

In particular embodiments, the social-networking system 160 may becapable of linking a variety of entities. As an example and not by wayof limitation, the social-networking system 160 may enable users tointeract with each other as well as receive content from third-partysystems 170 or other entities, or to allow users to interact with theseentities through an application programming interfaces (API) or othercommunication channels.

In particular embodiments, a third-party system 170 may include one ormore types of servers, one or more data stores, one or more interfaces,including but not limited to APIs, one or more web services, one or morecontent sources, one or more networks, or any other suitable components,e.g., that servers may communicate with. A third-party system 170 may beoperated by a different entity from an entity operating thesocial-networking system 160. In particular embodiments, however, thesocial-networking system 160 and third-party systems 170 may operate inconjunction with each other to provide social-networking services tousers of the social-networking system 160 or third-party systems 170. Inthis sense, the social-networking system 160 may provide a platform, orbackbone, which other systems, such as third-party systems 170, may useto provide social-networking services and functionality to users acrossthe Internet.

In particular embodiments, a third-party system 170 may include athird-party content object provider. A third-party content objectprovider may include one or more sources of content objects, which maybe communicated to a client system 130. As an example and not by way oflimitation, content objects may include information regarding things oractivities of interest to the user, such as, for example, movie showtimes, movie reviews, restaurant reviews, restaurant menus, productinformation and reviews, or other suitable information. As anotherexample and not by way of limitation, content objects may includeincentive content objects, such as coupons, discount tickets, giftcertificates, or other suitable incentive objects.

In particular embodiments, the social-networking system 160 alsoincludes user-generated content objects, which may enhance a user'sinteractions with the social-networking system 160. User-generatedcontent may include anything a user can add, upload, send, or “post” tothe social-networking system 160. As an example and not by way oflimitation, a user communicates posts to the social-networking system160 from a client system 130. Posts may include data such as statusupdates or other textual data, location information, photos, videos,links, music or other similar data or media. Content may also be addedto the social-networking system 160 by a third-party through a“communication channel,” such as a newsfeed or stream.

In particular embodiments, the social-networking system 160 may includea variety of servers, sub-systems, programs, modules, logs, and datastores. In particular embodiments, the social-networking system 160 mayinclude one or more of the following: a web server, action logger,API-request server, relevance-and-ranking engine, content-objectclassifier, notification controller, action log,third-party-content-object-exposure log, inference module,authorization/privacy server, search module, advertisement-targetingmodule, user-interface module, user-profile store, connection store,third-party content store, or location store. The social-networkingsystem 160 may also include suitable components such as networkinterfaces, security mechanisms, load balancers, failover servers,management-and-network-operations consoles, other suitable components,or any suitable combination thereof. In particular embodiments, thesocial-networking system 160 may include one or more user-profile storesfor storing user profiles. A user profile may include, for example,biographic information, demographic information, behavioral information,social information, or other types of descriptive information, such aswork experience, educational history, hobbies or preferences, interests,affinities, or location. Interest information may include interestsrelated to one or more categories. Categories may be general orspecific. As an example and not by way of limitation, if a user “likes”an article about a brand of shoes the category may be the brand, or thegeneral category of “shoes” or “clothing.” A connection store may beused for storing connection information about users. The connectioninformation may indicate users who have similar or common workexperience, group memberships, hobbies, educational history, or are inany way related or share common attributes. The connection informationmay also include user-defined connections between different users andcontent (both internal and external). A web server may be used forlinking the social-networking system 160 to one or more client systems130 or one or more third-party systems 170 via a network 110. The webserver may include a mail server or other messaging functionality forreceiving and routing messages between the social-networking system 160and one or more client systems 130. An API-request server may allow athird-party system 170 to access information from the social-networkingsystem 160 by calling one or more APIs. An action logger may be used toreceive communications from a web server about a user's actions on oroff the social-networking system 160. In conjunction with the actionlog, a third-party-content-object log may be maintained of userexposures to third-party-content objects. A notification controller mayprovide information regarding content objects to a client system 130.Information may be pushed to a client system 130 as notifications, orinformation may be pulled from a client system 130 responsive to arequest received from a client system 130. Authorization servers may beused to enforce one or more privacy settings of the users of thesocial-networking system 160. A privacy setting of a user determines howparticular information associated with a user can be shared. Theauthorization server may allow users to opt in to or opt out of havingtheir actions logged by the social-networking system 160 or shared withother systems (e.g., a third-party system 170), such as, for example, bysetting appropriate privacy settings. Third-party-content-object storesmay be used to store content objects received from third parties, suchas a third-party system 170. Location stores may be used for storinglocation information received from client systems 130 associated withusers. Advertisement-pricing modules may combine social information, thecurrent time, location information, or other suitable information toprovide relevant advertisements, in the form of notifications, to auser.

Social Graphs

FIG. 2 illustrates an example social graph 200. In particularembodiments, the social-networking system 160 may store one or moresocial graphs 200 in one or more data stores. In particular embodiments,the social graph 200 may include multiple nodes—which may includemultiple user nodes 202 or multiple concept nodes 204—and multiple edges206 connecting the nodes. The example social graph 200 illustrated inFIG. 2 is shown, for didactic purposes, in a two-dimensional visual maprepresentation. In particular embodiments, a social-networking system160, a client system 130, or a third-party system 170 may access thesocial graph 200 and related social-graph information for suitableapplications. The nodes and edges of the social graph 200 may be storedas data objects, for example, in a data store (such as a social-graphdatabase). Such a data store may include one or more searchable orqueryable indexes of nodes or edges of the social graph 200.

In particular embodiments, a user node 202 may correspond to a user ofthe social-networking system 160. As an example and not by way oflimitation, a user may be an individual (human user), an entity (e.g.,an enterprise, business, or third-party application), or a group (e.g.,of individuals or entities) that interacts or communicates with or overthe social-networking system 160. In particular embodiments, when a userregisters for an account with the social-networking system 160, thesocial-networking system 160 may create a user node 202 corresponding tothe user, and store the user node 202 in one or more data stores. Usersand user nodes 202 described herein may, where appropriate, refer toregistered users and user nodes 202 associated with registered users. Inaddition or as an alternative, users and user nodes 202 described hereinmay, where appropriate, refer to users that have not registered with thesocial-networking system 160. In particular embodiments, a user node 202may be associated with information provided by a user or informationgathered by various systems, including the social-networking system 160.As an example and not by way of limitation, a user may provide his orher name, profile picture, contact information, birth date, sex, maritalstatus, family status, employment, education background, preferences,interests, or other demographic information. In particular embodiments,a user node 202 may be associated with one or more data objectscorresponding to information associated with a user. In particularembodiments, a user node 202 may correspond to one or more webinterfaces.

In particular embodiments, a concept node 204 may correspond to aconcept. As an example and not by way of limitation, a concept maycorrespond to a place (such as, for example, a movie theater,restaurant, landmark, or city); a website (such as, for example, awebsite associated with the social-networking system 160 or athird-party website associated with a web-application server); an entity(such as, for example, a person, business, group, sports team, orcelebrity); a resource (such as, for example, an audio file, video file,digital photo, text file, structured document, or application) which maybe located within the social-networking system 160 or on an externalserver, such as a web-application server; real or intellectual property(such as, for example, a sculpture, painting, movie, game, song, idea,photograph, or written work); a game; an activity; an idea or theory;another suitable concept; or two or more such concepts. A concept node204 may be associated with information of a concept provided by a useror information gathered by various systems, including thesocial-networking system 160. As an example and not by way oflimitation, information of a concept may include a name or a title; oneor more images (e.g., an image of the cover page of a book); a location(e.g., an address or a geographical location); a website (which may beassociated with a URL); contact information (e.g., a phone number or anemail address); other suitable concept information; or any suitablecombination of such information. In particular embodiments, a conceptnode 204 may be associated with one or more data objects correspondingto information associated with concept node 204. In particularembodiments, a concept node 204 may correspond to one or more webinterfaces.

In particular embodiments, a node in the social graph 200 may representor be represented by a web interface (which may be referred to as a“profile interface”). Profile interfaces may be hosted by or accessibleto the social-networking system 160. Profile interfaces may also behosted on third-party websites associated with a third-party server 170.As an example and not by way of limitation, a profile interfacecorresponding to a particular external web interface may be theparticular external web interface and the profile interface maycorrespond to a particular concept node 204. Profile interfaces may beviewable by all or a selected subset of other users. As an example andnot by way of limitation, a user node 202 may have a correspondinguser-profile interface in which the corresponding user may add content,make declarations, or otherwise express himself or herself. As anotherexample and not by way of limitation, a concept node 204 may have acorresponding concept-profile interface in which one or more users mayadd content, make declarations, or express themselves, particularly inrelation to the concept corresponding to concept node 204.

In particular embodiments, a concept node 204 may represent athird-party web interface or resource hosted by a third-party system170. The third-party web interface or resource may include, among otherelements, content, a selectable or other icon, or other inter-actableobject (which may be implemented, for example, in JavaScript, AJAX, orPHP codes) representing an action or activity. As an example and not byway of limitation, a third-party web interface may include a selectableicon such as “like,” “check-in,” “eat,” “recommend,” or another suitableaction or activity. A user viewing the third-party web interface mayperform an action by selecting one of the icons (e.g., “check-in”),causing a client system 130 to send to the social-networking system 160a message indicating the user's action. In response to the message, thesocial-networking system 160 may create an edge (e.g., a check-in-typeedge) between a user node 202 corresponding to the user and a conceptnode 204 corresponding to the third-party web interface or resource andstore edge 206 in one or more data stores.

In particular embodiments, a pair of nodes in the social graph 200 maybe connected to each other by one or more edges 206. An edge 206connecting a pair of nodes may represent a relationship between the pairof nodes. In particular embodiments, an edge 206 may include orrepresent one or more data objects or attributes corresponding to therelationship between a pair of nodes. As an example and not by way oflimitation, a first user may indicate that a second user is a “friend”of the first user. In response to this indication, the social-networkingsystem 160 may send a “friend request” to the second user. If the seconduser confirms the “friend request,” the social-networking system 160 maycreate an edge 206 connecting the first user's user node 202 to thesecond user's user node 202 in the social graph 200 and store edge 206as social-graph information in one or more of data stores 164. In theexample of FIG. 2, the social graph 200 includes an edge 206 indicatinga friend relation between user nodes 202 of user “A” and user “B” and anedge indicating a friend relation between user nodes 202 of user “C” anduser “B.” Although this disclosure describes or illustrates particularedges 206 with particular attributes connecting particular user nodes202, this disclosure contemplates any suitable edges 206 with anysuitable attributes connecting user nodes 202. As an example and not byway of limitation, an edge 206 may represent a friendship, familyrelationship, business or employment relationship, fan relationship(including, e.g., liking, etc.), follower relationship, visitorrelationship (including, e.g., accessing, viewing, checking-in, sharing,etc.), sub scriber relationship, superior/subordinate relationship,reciprocal relationship, non-reciprocal relationship, another suitabletype of relationship, or two or more such relationships. Moreover,although this disclosure generally describes nodes as being connected,this disclosure also describes users or concepts as being connected.Herein, references to users or concepts being connected may, whereappropriate, refer to the nodes corresponding to those users or conceptsbeing connected in the social graph 200 by one or more edges 206.

In particular embodiments, an edge 206 between a user node 202 and aconcept node 204 may represent a particular action or activity performedby a user associated with user node 202 toward a concept associated witha concept node 204. As an example and not by way of limitation, asillustrated in FIG. 2, a user may “like,” “attended,” “played,”“listened,” “cooked,” “worked at,” or “watched” a concept, each of whichmay correspond to a edge type or subtype. A concept-profile interfacecorresponding to a concept node 204 may include, for example, aselectable “check in” icon (such as, for example, a clickable “check in”icon) or a selectable “add to favorites” icon. Similarly, after a userclicks these icons, the social-networking system 160 may create a“favorite” edge or a “check in” edge in response to a user's actioncorresponding to a respective action. As another example and not by wayof limitation, a user (user “C”) may listen to a particular song(“Imagine”) using a particular application (SPOTIFY, which is an onlinemusic application). In this case, the social-networking system 160 maycreate a “listened” edge 206 and a “used” edge (as illustrated in FIG.2) between user nodes 202 corresponding to the user and concept nodes204 corresponding to the song and application to indicate that the userlistened to the song and used the application. Moreover, thesocial-networking system 160 may create a “played” edge 206 (asillustrated in FIG. 2) between concept nodes 204 corresponding to thesong and the application to indicate that the particular song was playedby the particular application. In this case, “played” edge 206corresponds to an action performed by an external application (SPOTIFY)on an external audio file (the song “Imagine”). Although this disclosuredescribes particular edges 206 with particular attributes connectinguser nodes 202 and concept nodes 204, this disclosure contemplates anysuitable edges 206 with any suitable attributes connecting user nodes202 and concept nodes 204. Moreover, although this disclosure describesedges between a user node 202 and a concept node 204 representing asingle relationship, this disclosure contemplates edges between a usernode 202 and a concept node 204 representing one or more relationships.As an example and not by way of limitation, an edge 206 may representboth that a user likes and has used at a particular concept.Alternatively, another edge 206 may represent each type of relationship(or multiples of a single relationship) between a user node 202 and aconcept node 204 (as illustrated in FIG. 2 between user node 202 foruser “E” and concept node 204 for “SPOTIFY”).

In particular embodiments, the social-networking system 160 may createan edge 206 between a user node 202 and a concept node 204 in the socialgraph 200. As an example and not by way of limitation, a user viewing aconcept-profile interface (such as, for example, by using a web browseror a special-purpose application hosted by the user's client system 130)may indicate that he or she likes the concept represented by the conceptnode 204 by clicking or selecting a “Like” icon, which may cause theuser's client system 130 to send to the social-networking system 160 amessage indicating the user's liking of the concept associated with theconcept-profile interface. In response to the message, thesocial-networking system 160 may create an edge 206 between user node202 associated with the user and concept node 204, as illustrated by“like” edge 206 between the user and concept node 204. In particularembodiments, the social-networking system 160 may store an edge 206 inone or more data stores. In particular embodiments, an edge 206 may beautomatically formed by the social-networking system 160 in response toa particular user action. As an example and not by way of limitation, ifa first user uploads a picture, watches a movie, or listens to a song,an edge 206 may be formed between user node 202 corresponding to thefirst user and concept nodes 204 corresponding to those concepts.Although this disclosure describes forming particular edges 206 inparticular manners, this disclosure contemplates forming any suitableedges 206 in any suitable manner.

Search Queries on Online Social Networks

In particular embodiments, a user may submit a query to thesocial-networking system 160 by, for example, selecting a query input orinputting text into query field. A user of an online social network maysearch for information relating to a specific subject matter (e.g.,users, concepts, external content or resource) by providing a shortphrase describing the subject matter, often referred to as a “searchquery,” to a search engine. The query may be an unstructured text queryand may comprise one or more text strings (which may include one or moren-grams). In general, a user may input any character string into a queryfield to search for content on the social-networking system 160 thatmatches the text query. The social-networking system 160 may then searcha data store 164 (or, in particular, a social-graph database) toidentify content matching the query. The search engine may conduct asearch based on the query phrase using various search algorithms andgenerate search results that identify resources or content (e.g.,user-profile interfaces, content-profile interfaces, or externalresources) that are most likely to be related to the search query. Toconduct a search, a user may input or send a search query to the searchengine. In response, the search engine may identify one or moreresources that are likely to be related to the search query, each ofwhich may individually be referred to as a “search result,” orcollectively be referred to as the “search results” corresponding to thesearch query. The identified content may include, for example,social-graph elements (i.e., user nodes 202, concept nodes 204, edges206), profile interfaces, external web interfaces, or any combinationthereof. The social-networking system 160 may then generate asearch-results interface with search results corresponding to theidentified content and send the search-results interface to the user.The search results may be presented to the user, often in the form of alist of links on the search-results interface, each link beingassociated with a different interface that contains some of theidentified resources or content. In particular embodiments, each link inthe search results may be in the form of a Uniform Resource Locator(URL) that specifies where the corresponding interface is located andthe mechanism for retrieving it. The social-networking system 160 maythen send the search-results interface to the web browser 132 on theuser's client system 130. The user may then click on the URL links orotherwise select the content from the search-results interface to accessthe content from the social-networking system 160 or from an externalsystem (such as, for example, a third-party system 170), as appropriate.The resources may be ranked and presented to the user according to theirrelative degrees of relevance to the search query. The search resultsmay also be ranked and presented to the user according to their relativedegree of relevance to the user. In other words, the search results maybe personalized for the querying user based on, for example,social-graph information, user information, search or browsing historyof the user, or other suitable information related to the user. Inparticular embodiments, ranking of the resources may be determined by aranking algorithm implemented by the search engine. As an example andnot by way of limitation, resources that are more relevant to the searchquery or to the user may be ranked higher than the resources that areless relevant to the search query or the user. In particularembodiments, the search engine may limit its search to resources andcontent on the online social network. However, in particularembodiments, the search engine may also search for resources or contentson other sources, such as a third-party system 170, the internet orWorld Wide Web, or other suitable sources. Although this disclosuredescribes querying the social-networking system 160 in a particularmanner, this disclosure contemplates querying the social-networkingsystem 160 in any suitable manner.

Typeahead Processes and Queries

In particular embodiments, one or more client-side and/or backend(server-side) processes may implement and utilize a “typeahead” featurethat may automatically attempt to match social-graph elements (e.g.,user nodes 202, concept nodes 204, or edges 206) to informationcurrently being entered by a user in an input form rendered inconjunction with a requested interface (such as, for example, auser-profile interface, a concept-profile interface, a search-resultsinterface, a user interface/view state of a native applicationassociated with the online social network, or another suitable interfaceof the online social network), which may be hosted by or accessible inthe social-networking system 160. In particular embodiments, as a useris entering text to make a declaration, the typeahead feature mayattempt to match the string of textual characters being entered in thedeclaration to strings of characters (e.g., names, descriptions)corresponding to users, concepts, or edges and their correspondingelements in the social graph 200. In particular embodiments, when amatch is found, the typeahead feature may automatically populate theform with a reference to the social-graph element (such as, for example,the node name/type, node ID, edge name/type, edge ID, or anothersuitable reference or identifier) of the existing social-graph element.In particular embodiments, as the user enters characters into a formbox, the typeahead process may read the string of entered textualcharacters. As each keystroke is made, the frontend-typeahead processmay send the entered character string as a request (or call) to thebackend-typeahead process executing within the social-networking system160. In particular embodiments, the typeahead process may use one ormore matching algorithms to attempt to identify matching social-graphelements. In particular embodiments, when a match or matches are found,the typeahead process may send a response to the user's client system130 that may include, for example, the names (name strings) ordescriptions of the matching social-graph elements as well as,potentially, other metadata associated with the matching social-graphelements. As an example and not by way of limitation, if a user entersthe characters “pok” into a query field, the typeahead process maydisplay a drop-down menu that displays names of matching existingprofile interfaces and respective user nodes 202 or concept nodes 204,such as a profile interface named or devoted to “poker” or “pokemon,”which the user can then click on or otherwise select thereby confirmingthe desire to declare the matched user or concept name corresponding tothe selected node.

More information on typeahead processes may be found in U.S. patentapplication Ser. No. 12/763,162, filed 19 Apr. 2010, U.S. patentapplication Ser. No. 13/556,072, filed 23 Jul. 2012, U.S. patentapplication Ser. No. 14/470,607, filed 27 Aug. 2014, U.S. patentapplication Ser. No. 14/561,418, filed 5 Dec. 2014, and U.S. patentapplication Ser. No. 14/592,988, filed 9 Jan. 2015, which areincorporated by reference.

In particular embodiments, the typeahead processes described herein maybe applied to search queries entered by a user. As an example and not byway of limitation, as a user enters text characters into a query field,a typeahead process may attempt to identify one or more user nodes 202,concept nodes 204, or edges 206 that match the string of charactersentered into the query field as the user is entering the characters. Asthe typeahead process receives requests or calls including a string orn-gram from the text query, the typeahead process may perform or causeto be performed a search to identify existing social-graph elements(i.e., user nodes 202, concept nodes 204, edges 206) having respectivenames, types, categories, or other identifiers matching the enteredtext. The typeahead process may use one or more matching algorithms toattempt to identify matching nodes or edges. When a match or matches arefound, the typeahead process may send a response to the user's clientsystem 130 that may include, for example, the names (name strings) ofthe matching nodes as well as, potentially, other metadata associatedwith the matching nodes. The typeahead process may then display adrop-down menu that displays names of matching existing profileinterfaces and respective user nodes 202 or concept nodes 204, anddisplays names of matching edges 206 that may connect to the matchinguser nodes 202 or concept nodes 204, which the user can then click on orotherwise select thereby confirming the desire to search for the matcheduser or concept name corresponding to the selected node, or to searchfor users or concepts connected to the matched users or concepts by thematching edges. Alternatively, the typeahead process may simplyauto-populate the form with the name or other identifier of thetop-ranked match rather than display a drop-down menu. The user may thenconfirm the auto-populated declaration simply by keying “enter” on akeyboard or by clicking on the auto-populated declaration. Upon userconfirmation of the matching nodes and edges, the typeahead process maysend a request that informs the social-networking system 160 of theuser's confirmation of a query containing the matching social-graphelements. In response to the request sent, the social-networking system160 may automatically (or alternately based on an instruction in therequest) call or otherwise search a social-graph database for thematching social-graph elements, or for social-graph elements connectedto the matching social-graph elements as appropriate. Although thisdisclosure describes applying the typeahead processes to search queriesin a particular manner, this disclosure contemplates applying thetypeahead processes to search queries in any suitable manner.

In connection with search queries and search results, particularembodiments may utilize one or more systems, components, elements,functions, methods, operations, or steps disclosed in U.S. patentapplication Ser. No. 11/503,093, filed 11 Aug. 2006, U.S. patentapplication Ser. No. 12/977,027, filed 22 Dec. 2010, and U.S. patentapplication Ser. No. 12/978,265, filed 23 Dec. 2010, which areincorporated by reference.

Structured Search Queries

In particular embodiments, in response to a text query received from afirst user (i.e., the querying user), the social-networking system 160may parse the text query and identify portions of the text query thatcorrespond to particular social-graph elements. However, in some cases aquery may include one or more terms that are ambiguous, where anambiguous term is a term that may possibly correspond to multiplesocial-graph elements. To parse the ambiguous term, thesocial-networking system 160 may access a social graph 200 and thenparse the text query to identify the social-graph elements thatcorresponded to ambiguous n-grams from the text query. Thesocial-networking system 160 may then generate a set of structuredqueries, where each structured query corresponds to one of the possiblematching social-graph elements. These structured queries may be based onstrings generated by a grammar model, such that they are rendered in anatural-language syntax with references to the relevant social-graphelements. As an example and not by way of limitation, in response to thetext query, “show me friends of my girlfriend,” the social-networkingsystem 160 may generate a structured query “Friends of Stephanie,” where“Friends” and “Stephanie” in the structured query are referencescorresponding to particular social-graph elements. The reference to“Stephanie” would correspond to a particular user node 202 (where thesocial-networking system 160 has parsed the n-gram “my girlfriend” tocorrespond with a user node 202 for the user “Stephanie”), while thereference to “Friends” would correspond to friend-type edges 206connecting that user node 202 to other user nodes 202 (i.e., edges 206connecting to “Stephanie's” first-degree friends). When executing thisstructured query, the social-networking system 160 may identify one ormore user nodes 202 connected by friend-type edges 206 to the user node202 corresponding to “Stephanie”. As another example and not by way oflimitation, in response to the text query, “friends who work atfacebook,” the social-networking system 160 may generate a structuredquery “My friends who work at Facebook,” where “my friends,” “work at,”and “Facebook” in the structured query are references corresponding toparticular social-graph elements as described previously (i.e., afriend-type edge 206, a work-at-type edge 206, and concept node 204corresponding to the company “Facebook”). By providing suggestedstructured queries in response to a user's text query, thesocial-networking system 160 may provide a powerful way for users of theonline social network to search for elements represented in the socialgraph 200 based on their social-graph attributes and their relation tovarious social-graph elements. Structured queries may allow a queryinguser to search for content that is connected to particular users orconcepts in the social graph 200 by particular edge-types. Thestructured queries may be sent to the first user and displayed in adrop-down menu (via, for example, a client-side typeahead process),where the first user can then select an appropriate query to search forthe desired content. Some of the advantages of using the structuredqueries described herein include finding users of the online socialnetwork based upon limited information, bringing together virtualindexes of content from the online social network based on the relationof that content to various social-graph elements, or finding contentrelated to you and/or your friends. Although this disclosure describesgenerating particular structured queries in a particular manner, thisdisclosure contemplates generating any suitable structured queries inany suitable manner.

More information on element detection and parsing queries may be foundin U.S. patent application Ser. No. 13/556,072, filed 23 Jul. 2012, U.S.patent application Ser. No. 13/731,866, filed 31 Dec. 2012, and U.S.patent application Ser. No. 13/732,101, filed 31 Dec. 2012, each ofwhich is incorporated by reference. More information on structuredsearch queries and grammar models may be found in U.S. patentapplication Ser. No. 13/556,072, filed 23 Jul. 2012, U.S. patentapplication Ser. No. 13/674,695, filed 12 Nov. 2012, and U.S. patentapplication Ser. No. 13/731,866, filed 31 Dec. 2012, each of which isincorporated by reference.

Generating Keywords and Keyword Queries

In particular embodiments, the social-networking system 160 may providecustomized keyword completion suggestions to a querying user as the useris inputting a text string into a query field. Keyword completionsuggestions may be provided to the user in a non-structured format. Inorder to generate a keyword completion suggestion, the social-networkingsystem 160 may access multiple sources within the social-networkingsystem 160 to generate keyword completion suggestions, score the keywordcompletion suggestions from the multiple sources, and then return thekeyword completion suggestions to the user. As an example and not by wayof limitation, if a user types the query “friends stan,” then thesocial-networking system 160 may suggest, for example, “friendsstanford,” “friends stanford university,” “friends stanley,” “friendsstanley cooper,” “friends stanley kubrick,” “friends stanley cup,” and“friends stanlonski.” In this example, the social-networking system 160is suggesting the keywords which are modifications of the ambiguousn-gram “stan,” where the suggestions may be generated from a variety ofkeyword generators. The social-networking system 160 may have selectedthe keyword completion suggestions because the user is connected in someway to the suggestions. As an example and not by way of limitation, thequerying user may be connected within the social graph 200 to theconcept node 204 corresponding to Stanford University, for example bylike- or attended-type edges 206. The querying user may also have afriend named Stanley Cooper. Although this disclosure describesgenerating keyword completion suggestions in a particular manner, thisdisclosure contemplates generating keyword completion suggestions in anysuitable manner.

More information on keyword queries may be found in U.S. patentapplication Ser. No. 14/244,748, filed 3 Apr. 2014, U.S. patentapplication Ser. No. 14/470,607, filed 27 Aug. 2014, and U.S. patentapplication Ser. No. 14/561,418, filed 5 Dec. 2014, each of which isincorporated by reference.

Indexing Based on Object-type

FIG. 3 illustrates an example partitioning for storing objects ofsocial-networking system 160. A plurality of data stores 164 (which mayalso be called “verticals”) may store objects of social-networkingsystem 160. The amount of data (e.g., data for a social graph 200)stored in the data stores may be very large. As an example and not byway of limitation, a social graph used by Facebook, Inc. of Menlo Park,Calif. can have a number of nodes in the order of 10⁸, and a number ofedges in the order of 10¹⁰. Typically, a large collection of data suchas a large database may be divided into a number of partitions. As theindex for each partition of a database is smaller than the index for theoverall database, the partitioning may improve performance in accessingthe database. As the partitions may be distributed over a large numberof servers, the partitioning may also improve performance andreliability in accessing the database. Ordinarily, a database may bepartitioned by storing rows (or columns) of the database separately. Inparticular embodiments, a database maybe partitioned by based onobject-types. Data objects may be stored in a plurality of partitions,each partition holding data objects of a single object-type. Inparticular embodiments, social-networking system 160 may retrieve searchresults in response to a search query by submitting the search query toa particular partition storing objects of the same object-type as thesearch query's expected results. Although this disclosure describesstoring objects in a particular manner, this disclosure contemplatesstoring objects in any suitable manner.

In particular embodiments, each object may correspond to a particularnode of a social graph 200. An edge 206 connecting the particular nodeand another node may indicate a relationship between objectscorresponding to these nodes. In addition to storing objects, aparticular data store may also store social-graph information relatingto the object. Alternatively, social-graph information about particularobjects may be stored in a different data store from the objects.Social-networking system 160 may update the search index of the datastore based on newly received objects, and relationships associated withthe received objects.

In particular embodiments, each data store 164 may be configured tostore objects of a particular one of a plurality of object-types inrespective data storage devices 340. An object-type may be, for example,a user, a photo, a post, a comment, a message, an event listing, a webinterface, an application, a location, a user-profile interface, aconcept-profile interface, a user group, an audio file, a video, anoffer/coupon, or another suitable type of object. Although thisdisclosure describes particular types of objects, this disclosurecontemplates any suitable types of objects. As an example and not by wayof limitation, a user vertical P1 illustrated in FIG. 3 may store userobjects. Each user object stored in the user vertical P1 may comprise anidentifier (e.g., a character string), a user name, and a profilepicture for a user of the online social network. Social-networkingsystem 160 may also store in the user vertical P1 information associatedwith a user object such as language, location, education, contactinformation, interests, relationship status, a list of friends/contacts,a list of family members, privacy settings, and so on. As an example andnot by way of limitation, a post vertical P2 illustrated in FIG. 3 maystore post objects. Each post object stored in the post vertical P2 maycomprise an identifier, a text string for a post posted tosocial-networking system 160. Social-networking system 160 may alsostore in the post vertical P2 information associated with a post objectsuch as a time stamp, an author, privacy settings, users who like thepost, a count of likes, comments, a count of comments, location, and soon. As an example and not by way of limitation, a photo vertical P3 maystore photo objects (or objects of other media types such as video oraudio). Each photo object stored in the photo vertical P3 may comprisean identifier and a photo. Social-networking system 160 may also storein the photo vertical P3 information associated with a photo object suchas a time stamp, an author, privacy settings, users who are tagged inthe photo, users who like the photo, comments, and so on. In particularembodiments, each data store may also be configured to store informationassociated with each stored object in data storage devices 340.

In particular embodiments, objects stored in each vertical 164 may beindexed by one or more search indices. The search indices may be hostedby respective index server 330 comprising one or more computing devices(e.g., servers). The index server 330 may update the search indicesbased on data (e.g., a photo and information associated with a photo)submitted to social-networking system 160 by users or other processes ofsocial-networking system 160 (or a third-party system). The index server330 may also update the search indices periodically (e.g., every 24hours). The index server 330 may receive a query comprising a searchterm, and access and retrieve search results from one or more searchindices corresponding to the search term. In some embodiments, avertical corresponding to a particular object-type may comprise aplurality of physical or logical partitions, each comprising respectivesearch indices.

In particular embodiments, social-networking system 160 may receive asearch query from a PHP (Hypertext Preprocessor) process 310. The PHPprocess 310 may comprise one or more computing processes hosted by oneor more servers 162 of social-networking system 160. The search querymay be a text string or a search query submitted to the PHP process by auser or another process of social-networking system 160 (or third-partysystem 170). In particular embodiments, an aggregator 320 may beconfigured to receive the search query from PHP process 310 anddistribute the search query to each vertical. The aggregator maycomprise one or more computing processes (or programs) hosted by one ormore computing devices (e.g. servers) of the social-networking system160. Particular embodiments may maintain the plurality of verticals 164as illustrated in FIG. 3. Each of the verticals 164 may be configured tostore a single type of object indexed by a search index as describedearlier. In particular embodiments, the aggregator 320 may receive asearch request. For example, the aggregator 320 may receive a searchrequest from a PHP (Hypertext Preprocessor) process 210 illustrated inFIG. 2. In particular embodiments, the search request may comprise atext string. The search request may be a structured or substantiallyunstructured text string submitted by a user via a PHP process. Thesearch request may also be structured or a substantially unstructuredtext string received from another process of the social-networkingsystem. In particular embodiments, the aggregator 320 may determine oneor more search queries based on the received search request (step 303).In particular embodiments, each of the search queries may have a singleobject type for its expected results (i.e., a single result-type). Inparticular embodiments, the aggregator 320 may, for each of the searchqueries, access and retrieve search query results from at least one ofthe verticals 164, wherein the at least one vertical 164 is configuredto store objects of the object type of the search query (i.e., theresult-type of the search query). In particular embodiments, theaggregator 320 may aggregate search query results of the respectivesearch queries. For example, the aggregator 320 may submit a searchquery to a particular vertical and access index server 330 of thevertical, causing index server 330 to return results for the searchquery.

More information on indexes and search queries may be found in U.S.patent application Ser. No. 13/560,212, filed 27 Jul. 2012, U.S. patentapplication Ser. No. 13/560,901, filed 27 Jul. 2012, U.S. patentapplication Ser. No. 13/723,861, filed 21 Dec. 2012, and U.S. patentapplication Ser. No. 13/870,113, filed 25 Apr. 2013, each of which isincorporated by reference.

Customized Keyword Query Suggestions

In particular embodiments, the social-networking system 160 may providecustomized keyword query suggestions related to particular entities ofthe online social network. The social-networking system 160 may generatekeywords (e.g., words, phrases, other suitable text strings) byextracting n-grams from posts associated with a first entity, store thekeywords, and use the stored keywords to generate keyword querysuggestions associated with the first entity. The keyword querysuggestions may then be provided to a second entity (e.g., a userconducting a search) of the online social network to facilitate thesecond entity's search related to the first entity. Here, an entity maybe a user, a group of users, an organization, a place, a website, oranother suitable entity, which is capable of being represented in thesocial-networking system 160 or a third-party system 170. The socialgraph 200 may comprise a plurality of entity nodes corresponding to aplurality of entities associated with the online social network,including the first entity and the second entity. Posts associated withthe first entity may include data such as, for example, status updatesor other textual data, location information, photos, videos, links,music, other suitable data or media, or any combination thereof. Thesocial graph 200 may comprise a plurality of content nodes correspondingto a plurality of posts (or other content) on the online social network,including posts of the first entity. Each content node may be connectedto one or more of the entity nodes by one or more edges 206 on thesocial graph 200. As an example and not by way of limitation, a queryinguser, who is a friend of the user “Xiao” on the online social network,may be visiting a profile interface associated with Xiao and decide toconduct a search from the current profile interface. Thesocial-networking system 160 may have extracted a plurality of n-gramsfrom one or more posts associated with Xiao, and generated, ranked, andcached a set of keywords in relation to Xiao ahead of time. Thesocial-networking system 160 may then provide a list of suggestedkeyword queries to the querying user, each suggested keyword queryincorporating one or more of the top-ranked keywords. The querying usermay be able to select and use one of the suggested keyword queries toconduct a search, which may retrieve one or more posts or contentobjects of other types associated with Xiao. As another example and notby way of limitation, a querying user, who follows a public figure“Mark” on the online social network, may conduct a search from anewsfeed interface of the querying user. The querying user may type astring or partial query “Mar” in a query field. The social-networkingsystem 160 may use one or more matching algorithms (e.g., matchingalgorithms used in the typeahead processes described previously) toidentify entities of the online social network that match this partialquery. The entity Mark may be identified as such a match. Thesocial-networking system 160 may then provide a list of suggestedkeyword queries for the querying user to select and use, each suggestedkeyword query incorporating one or more keywords generated based onposts associated with Mark. The embodiments described herein may enablethe social-networking system 160 to provide suggested queries that arecustomized for particular entities and, at the same time, may reduce oreliminate the chance that a suggested query provided by thesocial-networking system 160 retrieves a set comprising no results(e.g., a null set). Although this disclosure describes providingparticular customized keyword query suggestions related to particularentities in a particular manner, this disclosure contemplates providingany suitable customized keyword query suggestions related to anysuitable entities in any suitable manner.

In particular embodiments, the social-networking system 160 may access aplurality of posts of an online social network. Each post may beassociated with a particular entity of the online social network. Theposts may be stored in one or more data stores 164 of thesocial-networking system 160. The social-networking system 160 mayidentify a plurality of entities of the online social network for whichto generate keyword query suggestions. The identified entities mayinclude all entities of the online social network, or a selected subsetof entities. They may be chosen based on, for example, a number of postsassociated with each entity, a frequency of activity of the entity onthe online social network (e.g., how frequently a user posts), afrequency that information about each entity is being searched, anothersuitable factor, or any combination thereof. The social-networkingsystem 160 may access the posts associated with the particular entityoffline according to a specified schedule (e.g., once a day).Alternatively, the social-networking system 160 may access a new post ofthe particular entity offline whenever the new post is made available onthe online social network. The social-networking system 160 may alsoaccess posts of the particular entity in real time, when it is necessaryto provide keyword query suggestions related to the particular entity(e.g., responsive to a user accessing a profile page of the particularentity). As an example and not by way of limitation, thesocial-networking system 160 may determine that the public figure Markis popular on the online social network and that it is desirable togenerate keyword query suggestions in relation to Mark. Thesocial-networking system 160 may place a listener on a profile interfaceassociated with Mark, wherein the listener may monitor and report, tothe social-networking system 160, events occurring in relation to theprofile interface. The social-networking system 160 may then access eachpost on the profile interface, in response to a report from thelistener, as soon as the post is made available there. As anotherexample and not by way of limitation, the social-networking system 160may provide keyword query suggestions for all entities of the onlinesocial network, including the entity Xiao. The social-networking system160 may access all posts associated with Xiao once a day to detectnewly-created posts. If so, the social-networking system 160 may accessany such newly-created posts.

In particular embodiments, the accessed posts may comprise postsgenerated within a specified timeframe. The social-networking system 160may select posts to access based on specified rules. The rules may beguided by both an interest in using only the most relevant posts and aninterest in ensuring a sufficiently large corpus from which to extractkeywords. The rules may be time-based. For a particular entity, thesocial-networking system 160 may be configured to access only postsassociated with the entity that are generated in a particular timeperiod. The timeframe may be uniform with respect to all entities of theonline social network or be specifically determined for each entity oreach type of entities. As an example and not by way of limitation, thesocial-networking system 160 may access only posts associated with Xiaothat are made available on the online social network within three monthsbefore the time of access. As another example and not by way oflimitation, the public figure Mark may be more active on the onlinesocial network than Xiao. Accordingly, the social-networking system 160may access posts associated with Mark that are generated within narrowertime period (e.g., the past one week), which still allows for asufficiently large corpus of posts from which to extract keywords.

In particular embodiments, the number of posts accessed by thesocial-networking system 160 may be the smaller of a specified number ofposts or a total number of posts associated with a particular entity ofthe online social network. In order to ensure a sufficiently largecorpus from which to extract keywords, the social-networking system 160may be configured to access a specified minimum number of postsassociated with each entity. This specified minimum number may beuniform with respect to all entities of the online social network or bespecifically determined for each entity or each type of entities. It maybe pre-determined as a target or dynamically generated. For a particularentity, if a total number of posts associated with the entity is smallerthan the specified minimum number (e.g., because the user is a new userof the online social network, or an infrequent poster on the onlinesocial network), the social-networking system 160 may access all postsassociated with the entity to obtain a corpus that is as large aspossible. Configurations about the number of posts to access may becombined with configurations about the timeframe associated withaccessed posts. For example, for a particular entity, thesocial-networking system 160 may be configured to access posts generatedin relation to the entity within a specified time period if and only ifthe number of posts generated in this period exceeds a specified minimumnumber. Otherwise, the social-networking system 160 may access theminimum number of most recent posts associated with the entityregardless of whether each post is generated within the specified period(or a total number of posts associated with the entity if this totalnumber is smaller than the specified minimum number). As an example andnot by way of limitation, the social-networking system 160 may beconfigured to access a minimum number of 30 posts associated with anordinary user, such as Xiao, of the online social network. Because thereare only 25 posts associated with Xiao on the online social network, thesocial-networking system 160 may access all posts of Xiao regardless ofthe time each accessed post was generated. As another example and not byway of limitation, the social-networking system 160 may be configured toaccess a minimum number of 100 posts associated with a public figure,such as Mark. It may be determined that 2000 posts have been generatedin relation to Mark within a specified timeframe (e.g., the past oneyear). Because this number exceeds the specified minimum number, thesocial-networking system 160 may only access the posts within thespecified timeframe. Alternatively, the social-networking system 160 mayonly access 100 most recent posts associated with Mark.

In particular embodiments, the accessed posts related to a particularentity may include posts authored by the particular entity, postsauthored by one or more other entities within a threshold degree ofseparation of the particular entity in the social graph, posts added tothe online social network by one or more other entities referencing theparticular entity, or posts added to a profile interface of theparticular entity on the online social network by one or more otherentities. The scope of posts to access may be uniform with respect toall entities of the online social network or be specifically determinedfor each entity or each type of entities. For a particular entity, thesocial-networking system 160 may determine a scope of posts to access.This determination may be based on, for example, a number of each typeof posts associated with the entity, the relevance of each type of poststo the entity, the cost or difficulty in accessing each type of posts,another suitable factor, or any combination thereof. As an example andnot by way of limitation, the social-networking system 160 may beconfigured to preferentially access posts authored by a particularentity, which may be most relevant to the entity. Xiao, however, mayhave only authored 5 posts during her entire history of using the onlinesocial network. In order to obtain a sufficiently large corpus fromwhich to generate keywords associated with Xiao, the social-networkingsystem 160 may extend the scope of access to other types of posts, suchas posts authored by Xiao's friends on the online social network andposts referencing Xiao. As another example and not by way of limitation,there may be a large number of posts added to the online social networkby third-party entities referencing the public figure Mark. Thesocial-networking system 160 may only access posts that are added to aprofile interface of Mark with Mark's permission. Although thisdisclosure describes accessing particular posts of an online socialnetwork in a particular manner, this disclosure contemplates accessingany suitable posts of an online social network in any suitable manner.

In particular embodiments, the social-networking system 160 may generatea plurality of candidate keywords for suggested queries by extractingone or more n-grams from content of the accessed posts. The candidatekeywords may be generated prior to a search attempt by a querying uservia an offline process (e.g., pre-generated) or in response to a queryin real time (e.g., dynamically generated in response to a useraccessing a query field or inputting a query). The social-networkingsystem 160 may extract the n-grams using a phrase-extraction algorithm.The phrase-extraction algorithm may function based on one or more rules,one or more of which may be associated with language features such assentence structures and word types. The social-networking system 160 mayextract one or more n-grams from each of one or more of the accessedposts and aggregate the extracted n-grams to form a pool of candidatekeywords. Alternatively, the social-networking system 160 may combinethe content of the accessed posts into a corpus and directly generateone or more candidate keywords by extracting n-grams from the corpus. Asan example and not by way of limitation, the entity Xiao may have posteda status update “Look at my new Tesla” after purchasing a Tesla car. Thesocial-networking system 160 may analyze the text string and determinethat the n-gram “Tesla” is the only noun in this one-sentence statusupdate. It may generate a candidate keyword “Tesla” by extracting then-gram from Xiao's status update. As another example and not by way oflimitation, the social-networking system 160 may combined all contentfrom posts associated with Mark within a specified timeframe into acorpus and determine that the n-gram “oculus” appears multiple times inthe corpus. Based on this determination, the social-networking system160 may generate the keyword “oculus” by extracting the n-gram from thecorpus. In connection with keyword extraction and generation, particularembodiments may utilize one or more systems, components, elements,functions, methods, operations, or steps disclosed in U.S. patentapplication Ser. No. 14/797,819, filed 13 Jul. 2015 and U.S. patentapplication Ser. No. 14/938,685, filed 11 Nov. 2015, each of which isincorporated by reference.

In particular embodiments, generating the plurality of candidatekeywords may comprise extracting one or more n-grams from the content ofthe accessed posts, calculating a relevance score for each extractedn-gram based on TF-IDF analysis, and generating a candidate keywordcorresponding to each n-gram having a calculated relevance score greaterthan a threshold relevance score. As an example and not by way oflimitation, the social-networking system 160 may extract 10 n-grams fromthe content of Xiao's posts and perform TF-IDF analysis on the extractedn-grams. The 10 extracted n-grams may each be assigned a relevance scoreon a scale from 0 to 1. The social-networking system 160 may thengenerate a candidate keyword for each extracted n-gram that has arelevance score higher than 0.5.

In particular embodiments, generating the plurality of candidatekeywords may further comprise accessing one or more images associatedwith each of one or more of the accessed posts, identifying one or moren-grams corresponding to one or more features of each accessed image,and generating a candidate keyword for each of one or more of theidentified n-grams. A media item may be translated into text by usingsoftware to recognize text within the media item. For a particular imagefile comprising an image, the social-networking system 160 may analyzeimage characteristics such as pixel values or gradients to determineshapes. The social-networking system 160 may then recognize persons(e.g., a particular user of the online social network) or concepts(e.g., the Eiffel Tower) that the image represents and thereby translatethe image into text describing the person (e.g., a name of the user,“John Smith,” descriptors of the user, “male,” “26-year-old”) or textdescribing the concept (e.g., “Eiffel Tower,” “France”). For aparticular image file comprising text (e.g., a scanned image of adocument), the social-networking system 160 may useoptical-character-recognition software to recognize text within thefile. As an example and not by way of limitation, Xiao may have posted aphoto of herself on the online social network along with the comment“See where I am.” The photo may be taken in France and may have theEiffel Tower as background. The social-networking system 160 mayrecognize the unique shape of the Eiffel Tower as a feature of the photoand identify the n-gram “Eiffel Tower” based on this feature, eventhough the n-gram “Eiffel Tower” may not literally appear in any textposted by Xiao. More information about analyzing images to recognizepersons or concepts may be found in U.S. patent application Ser. No.13/959,446, filed 5 Aug. 2013, and U.S. patent application Ser. No.14/983,385, filed 29 Dec. 2015, which are incorporated by reference.Although this disclosure describes generating candidate keywords in aparticular manner, this disclosure contemplates generating candidatekeywords in any suitable manner.

In particular embodiments, the social-networking system 160 maycalculate a rank for each candidate keyword based at least in part on anumber of social signals associated with the post from which the n-gramcorresponding to the candidate keyword was extracted. A number ofcandidate keywords generated by extracting n-grams from posts associatedwith a particular entity may exceed a number of keyword querysuggestions that can be stored or provided in association with theparticular entity. This may necessitate ranking the candidate keywords,such that one or more candidate keywords (e.g., those determined to bemost helpful or relevant) may be selected to be presented to a queryinguser. The rank for each candidate keyword may correspond to a priorityfor being presented to a querying user as part of a keyword querysuggestion. A candidate keyword with a higher rank may be more likely tobe suggested to a querying user or be presented in a more noticeableposition of a user interface associated with the online social networkthan a candidate keyword with a lower rank. Calculating the rank foreach candidate keyword may be based on a variety of factors, including,for example, social signals, language features, recency, repetition,other suitable factors, or any combination thereof. In particularembodiments, the social signals associated with each post may comprisean accessing or viewing of the post, a comment on the post, a sharing ofthe post, a liking of the post, a liking of the comment on the post, aliking of the sharing of the post, other suitable social actions on theonline social network, or any combination thereof. The social-networkingsystem 160 may access one or more data stores 164 to obtain records ofthe social signals. The social signals may be filtered based on one ormore factors, such as a specified timeframe. As an example and not byway of limitation, the social-networking system 160 may have generatedtwo keywords “Tesla” and “gravitational waves” that are associated withXiao. The keyword “Tesla” may be extracted from Xiao's status updateabout her new car, which has been viewed by 100 users, commented on by15 users, and liked by 50 users. The keyword “gravitational waves” maybe extracted from Xiao's comment on a shared article discussing thediscovery of gravitational waves, which has been viewed by 90 users,commented on by 5 users, and liked by 30 users. The social-networkingsystem 160 may thereby assign “Tesla” a higher rank than “gravitationalwaves” because social signals suggest that the post from which “Tesla”was extracted is more socially relevant than the post from which“gravitational waves” was extracted. As another example and not by wayof limitation, the social-networking system 160 may have generated twokeywords “ai” and “oculus” based on keywords extracted from Mark'sposts. Because Mark is a public figure on the online social network, hisposts are shared by a large number of other entities. Thesocial-networking system 160 may access social-networking informationassociated with Mark and determine that the post associated with “ai”has been shared 2,000 times and the post associated with “oculus” hasbeen shared 1,000 times within the past hour. The social-networkingsystem 160 may thereby assign a higher rank to “ai” than “oculus” basedon this determination. More information on social signals may be foundin U.S. patent application Ser. No. 14/640,461, filed 6 Mar. 2015, whichis incorporated by reference.

In particular embodiments, the social-networking system 160 maycalculate the rank for each candidate keyword further based on analysisof the candidate keyword according to a language model. The languagemodel may be trained by a training data set comprising a large number ofposts of the online social network. The social-networking system 160 mayweigh the strength of each candidate keyword based on one or morefactors considered by the language model (e.g., a language model score,an IDF score, a TF-IDF score). Particular language models may be capableof deriving a strength of a particular candidate keyword that does notappear in its training data set based on the strengths of the candidatekeyword's component n-grams. As an example and not by way of limitation,the social-networking system 160 may have generated the candidatekeywords “ai” and “internet.org” based on Mark's posts. Based on alanguage model used by the social-networking system 160, “ai” may bedetermined to be stronger than “internet.org” (e.g., at least in partbecause “ai” appears more often than “internet.org” in a training dataset comprising a large number of posts of the online social network).The social-networking system 160 may thereby calculate a higher rank for“ai” than “internet.org.” In particular embodiments, thesocial-networking system 160 may calculate the rank for each candidatekeyword further based on a length of the candidate keyword. It may bedesirable for the social-networking system 160 to provide keyword querysuggestions that have clear and independent meanings rather thanambiguous or incomplete meanings. Therefore, the social-networkingsystem 160 may be configured to preferentially rank candidate keywordsthat are longer n-grams (e.g., bi-grams, tri-grams) with independentmeaning over candidate keywords that are shorter n-grams (e.g.,uni-grams) with unclear or ambiguous meaning (e.g., the relevance of auni-gram as a keyword query suggestion may be unclear because of theuni-gram lacks the context of the content from which it was extracted).As an example and not by way of limitation, the social-networking system160 may calculate a higher rank for “refugee crisis,” which is a bi-gramwith a relatively clear and independent meaning, than for “oculus,”which is a uni-gram brand name.

In particular embodiments, the social-networking system 160 maycalculate the rank for each candidate keyword further based on a time ofcreation associated with the post from which the n-gram corresponding tothe candidate keyword was extracted. It may be the case that content ina post more recently created is more likely to be searched for thancontent in a post less recently created. As an example and not by way oflimitation, the social-networking system 160 may rank the keyword“Tesla” higher than the keyword “gravitational waves” because “Tesla” isextracted from a post more recently added to the online social networkby Xiao.

In particular embodiments, calculating the rank for each candidatekeyword may comprise determining that a particular candidate keywordappears in a list of trending-topic keywords and up-ranking theparticular candidate keyword based on the determination. Thesocial-networking system 160 may generate and maintain a list oftrending-topic keywords (e.g., hashtags, known topic phrases)representing popular words or phrases on the online social network. Thislist may be generated by searching through posts recently added to theonline social network and identifying words and phrases that are mostfrequently used by entities of the online social network. Whether aparticular word or phrase may be added to the list may also depend on,for example, the entities that use the word or phrase, a time-basedpattern of use, another suitable factor, or any combination thereof. Thelist of trending-topic keywords may also be customizable for particularentities of the online social network. For example, for a particularquerying user, the list of trending-topic keywords may comprise words orphrases that are popular among friends or friends of friends of theparticular querying user on the online social network. The list oftrending-topic keywords may be updated regularly based on a specifiedschedule or dynamically based on events occurring on the online socialnetwork. As an example and not by way of limitation, thesocial-networking system 160 may calculate a higher rank for the keyword“gravitational waves” than “Tesla” because the former appears in a listof trending-topic keywords after the recent publication of relatedscientific discoveries.

In particular embodiments, calculating the rank for each candidatekeyword may comprise determining that a particular candidate keywordappears in more than one accessed posts associated with the particularentity of the online social network, calculating a number of accessedposts comprising the candidate keyword, and up-ranking the candidatekeyword based on the calculated number of accessed posts. It may bedesirable to configure the social-networking system 160 in a way suchthat, for a particular entity, a word or phrase appearing in multipleposts of the entity is preferentially ranked. As an example and not byway of limitation, Xiao may be excited about her new car and havepublished 5 posts containing the word “Tesla.” She may only have sharedone post about the discovery of gravitational waves. Although thekeyword “gravitational waves” may be ranked higher than “Tesla” based onother criteria, the social-networking system 160 may nonethelessdetermine that “Tesla” appears in more than one accessed postsassociated with Xiao, calculate that 5 posts comprise the keyword, andup-rank “Tesla” to a higher rank than “gravitational waves.”

In particular embodiments, calculating the rank for each candidatekeyword may comprise, for a first candidate keyword, determining thatone or more n-grams corresponding to a particular number of othercandidate keywords, respectively, were extracted from the post fromwhich the n-gram corresponding to the first candidate keyword wasextracted, determining that the particular number of other candidatekeywords each has a higher rank than the first candidate keyword, anddown-ranking the first candidate keyword based on the determinations. Itmay be desirable to configure the social-networking system 160 in a waysuch that keywords generated based on a diverse variety of postsassociated with a particular entity are provided as part of keywordquery suggestions. Doing so may contribute to ensuring that each of thequery suggestions retrieves a unique set of results. This may requirelimiting the number of highly ranked keywords generated based on eachpost. The social-networking system 160 may, accordingly, set a cap foreach post specifying a maximum number of keywords that may be generatedbased on the post. Alternatively, the social-networking system 160 maydown-rank keywords generated based on a particular post when the posthas provided multiple n-grams corresponding to other highly rankedkeywords. As an example and not by way of limitation, thesocial-networking system 160 may have extracted the n-grams “ai,”“internet.org,” “connectivity,” and “free basics” all from one of Mark'sposts. Because of the popularity of this post, all four keywords basedon the extracted n-grams may be ranked top four based on other rankingcriteria. In this situation, the social-networking system 160 maydetermine that “ai” and “internet.org” are both generated based on thesame post as and ranked higher than “connectivity” and “free basics,”and down-rank at least “connectivity” and “free basics” accordingly.This allows keywords generated from other posts, such as “refugeecrisis” and “oculus,” to be provided as part of keyword querysuggestions associated with Mark. Although this disclosure describescalculating ranks for candidate keywords in a particular manner, thisdisclosure contemplates calculating ranks for candidate keywords in anysuitable manner.

In particular embodiments, the social-networking system 160 may storeone or more candidate keywords in association with the first entity.Each stored candidate keyword may have a calculated rank higher than athreshold rank. Because a large number of candidate keywords may begenerated for each entity, it may be costly and inefficient for thesocial-networking system 160 to store all such candidate keywords.Instead, after ranking the candidate keywords generated in relation toan entity, the social-networking system 160 may only store or cache oneor more top-ranked candidate keywords associated with the entity. Thethreshold rank may depend on the number of candidate keywords thesocial-networking system 160 stores in association with each entity.This number may be uniform with respect to all entities of the onlinesocial network or be specifically determined for each entity or eachtype of entities. It may be specified based on a number of post-basedkeyword query suggestions that can be provided in a single instance ofsearch. In particular embodiments, the candidate keywords may be storedin one or more data stores 164 associated with the online socialnetwork. Alternatively, they may be stored on a local cache of a clientsystem 130 of the second entity (e.g., a user conducting a search aboutthe entity). The social-networking system 160 may select and rank one ormore entities, information associated with which are to be cached on theclient system 130 of the second entity. Candidate keywords associatedwith all or a specified number of top-ranked cached entities may becached on the client system 130. The selection and ranking of cachedentities may be based on, for example, a relationship or affinitycoefficient between each entity and the second entity on the onlinesocial network, a search history of the second entity, a browsinghistory of the second entity, another suitable criterion, or anycombination thereof. The local cache may be associated with a webbrowser 132 of the client system 130. The candidate keywords may bestored on the local cache when the client system 130 is turned on, a webpage associated with the online social network is opened on the webbrowser 132, or when an application installed on the client system 130that is associated with the online social network is opened. Keywordquery suggestions associated with the cached entities may be provided tothe second entity nearly instantaneously form the local cache. Thestored candidate keywords may be updated periodically according to aspecified schedule (e.g., once an hour). Alternatively, the storedcandidate keywords may be updated dynamically based on one or more typesof trigger events (e.g., a new search conducted by the second entity).As an example and not by way of limitation, the social-networking system160 may have generated and ranked 100 candidate keywords associated withMark. The social-networking system 160 may store 10 top-ranked candidatekeywords associated with Mark in a data store 164 configured to storecandidate keywords that are generated based on entities' posts. Thesocial-networking system 160 may monitor a profile interface associatedwith Mark to detect any new post being added to the profile interfaceand, upon detection of a new post, update the candidate keywords storedin association with Mark. As another example and not by way oflimitation, the social-networking system 160 may select and rank severalentities including Xiao, whose information is to be cached on a clientsystem 130 of the second entity. In particular, Xiao may be selectedbecause she has a high affinity coefficient with the second entity andthat the second entity recently visited Xiao's profile interface. Thesocial-networking system 160 may store 5 candidate keywords associatedwith Xiao on a local cache of the client system 130. The 5 cachedcandidate keywords may be updated every hour. Subsequently, the secondentity may conduct a search about one or more other entities. Based onthe second entity's activities, the social-networking system 160 mayupdate the entities to be cached on the client system 130, which may nolonger include Xiao. The social-networking system 160 may then cause thecandidate keywords associated with Xiao to be deleted from the clientsystem 130.

In particular embodiments, each accessed post may be associated with aprivacy setting defining a visibility of the post that is visible to atleast the second entity. The social-networking system 160 may store, fora particular entity, more than one set of candidate keywords associatedwith the entity. Each set of candidate keywords may correspond to one ormore privacy groups of entities (e.g., friends, friends of friends,public) with respect to the entity associated with the candidatekeywords. Different sets may share one or more common candidatekeywords. A particular candidate keyword may be placed in one or moresets based on privacy settings associated with the post from which then-gram corresponding to the candidate keyword was extracted. To enforcethe privacy settings, keyword query suggestions being provided to aparticular entity may only comprise candidate keywords generated basedon n-grams extracted from posts that are visible to the particularentity. As an example and not by way of limitation, thesocial-networking system 160 may store two sets of candidate keywords inassociation with Xiao. A first set may comprise 5 candidate keywordseach corresponding to an n-gram extracted from posts associated withXiao that are visible to the public. A second set may comprise 5candidate keywords each corresponding to an n-gram extracted from postsassociated with Xiao that are either visible to the public or visibleonly to Xiao's friends. It may be the case that one or more top-rankedcandidate keywords in the first set are included in the second set. Akeyword query suggestion comprising a candidate keyword in the first setmay be provided to any entity of the online social network. On the otherhand, a keyword query suggestion comprising a candidate keyword in thesecond set may be provided only to friends of Xiao on the online socialnetwork. Although this disclosure describes storing candidate keywordsin association with the first entity in a particular manner, thisdisclosure contemplates storing candidate keywords in association withthe first entity in any suitable manner.

In particular embodiments, the social-networking system 160 may send, toa client system 130 of the second entity of the online social network,one or more suggested queries associated with the first entity fordisplay on the client system 130. Each suggested query may comprise oneor more of the stored candidate keywords associated with the firstentity. Upon determining a need to provide one or more keyword querysuggestions, the social-networking system 160 may access one or morestored candidate keywords and generate one or more keyword querysuggestions based on the accessed candidate keywords. In particularembodiments, the social-networking system 160 may generate a suggestedkeyword query by combining a candidate keyword with one or more othern-grams. Specifically, a suggested keyword query may be generated inassociation with a particular first entity by combining a storedcandidate keyword with a reference to the first entity (e.g., “XiaoTesla”). Alternatively, a suggested keyword query generated by thesocial-networking system 160 may comprise only a candidate keyword(e.g., “Tesla”). A suggested keyword query may be generated locally onthe client system 130 of the second entity and be made available fordisplay on the client system 130. Alternatively, the suggested keywordquery may be generated on a server 162 associated with thesocial-networking system 160 and be sent to the client system 130 of thesecond entity for display over a network 110. The suggested keywordqueries generated based on candidate keywords associated with the firstentity may be combined with suggested queries generated based on othersources (e.g., a search history associated with the second entity,content associated with the second entity, trending or popular topics onthe online social network) and collectively sent to the client system130 of the second entity for display. Doing so may allow the secondentity to receive a relatively comprehensive set of query suggestions.In particular embodiments, a suggested keyword query may be sent fordisplay on a webpage associated with the online social network accessedby a browser client 132 on the client system 130 of the second entity.The suggested keyword query may alternatively be displayed in a userinterface associated with an application corresponding to thesocial-networking system 160 that is installed on the client system 130of the second entity. As an example and not by way of limitation, thesocial-networking system 160 may have caused the second entity's clientsystem 130 to cache a set of candidate keywords associated with Xiao,including the candidate keyword “Tesla.” The social-networking system160 may instruct an application installed on the client system 130 togenerate a suggested keyword query “Xiao Tesla” by combining the keywordwith a reference to Xiao. The application may then provide thissuggested keyword query to the second entity by displaying it in a userinterface associated with the application. As another example and not byway of limitation, the social-networking system 160 may have stored aset of candidate keywords associated with the public figure Mark on theonline social network, including the candidate keyword “internet.org.”The social-networking system 160 may accordingly generate the suggestedkeyword query “internet.org” and send it to the client device 130 of thesecond entity for display.

In particular embodiments, the social-networking system 160 may furtherdetermine that the second entity is currently accessing, via the clientsystem 130, an interface of the online social network associated with anentity node corresponding to the first entity. If the second entityinitiates a search by, for example, clicking on a query field that ispart of an interface associated with the first entity, it may be likelythat the second entity is interested in searching for content associatedwith the first entity. Based on the determination, the social-networkingsystem 160 may provide the second entity one or more suggested queriescomprising one or more candidate keywords associated with the firstentity. As an example and not by way of limitation, the second entitymay click on the query field while browsing Xiao's profile interface. Inresponse, the social-networking system 160 may provide, for example, ina dropdown menu, a list of suggested queries comprising candidatekeywords associated with Xiao. More information on providing suggestedqueries based on access of an entity's interface may be found in U.S.patent application Ser. No. 13/732,175, filed 31 Dec. 2012, which isincorporated by reference. In particular embodiments, thesocial-networking system 160 may further access a search historyassociated with the second entity, the search history comprising aplurality of queries. At least one of the queries of the search historymay be associated with an entity node corresponding to the first entity.It may be the case that an entity tends to conduct searches that arerelated to the entity's previous searches. The social-networking system160 may therefore provide keyword query suggestions based on the secondentity's search history. As an example and not by way of limitation, thesecond entity may click on a query field while browsing the secondentity's own newsfeed interface, which displays content items (e.g.,posts) associated with the second entity's social connections. Thesocial-networking system 160 may access a search history of the secondentity, determine that the second entity has recently searched for Xiaoand Mark, and provide for display on a client device 130 of the secondentity several suggested keyword queries comprising candidate keywordsassociated with each of Xiao and Mark. In particular embodiments, thesocial-networking system 160 may further receive, from the client systemof the second entity, an unstructured text query, parse the text queryto identify one or more n-grams, and determine that at least one of theidentified n-grams corresponds to an entity node corresponding to thefirst entity. As an example and not by way of limitation, the secondentity may type, in a query field, the text string “Xia”. Thesocial-networking system 160, with its typeahead feature, may parse thispartial text query, determine that it corresponds to an entity nodeassociated with the entity Xiao, and provide one or more suggestedkeyword queries comprising candidate keywords associated with Xiao tothe second entity. Although this disclosure describes sending suggestedqueries for display in a particular manner, this disclosure contemplatessending suggested queries for display in any suitable manner.

FIG. 4 illustrates an example profile interface for displaying keywordquery suggestions. In this example, the profile interface and the querysuggestions both correspond to the same entity. In particularembodiments, a second entity may visit a profile interface 400associated with Mark, a public figure on the online social network andinitiate a search from this interface by clicking on the query field410. The social-networking system 160 may determine that the secondentity is currently accessing the profile interface 400 of Mark and mayautomatically fill the query field 410 with the term “Mark.” When thesecond entity clicks on the query field 410, a dropdown menu 420comprising a list of suggested queries may be displayed. The list maycomprise content type queries 430, each, if executed by a search engine,may search the online social network for a particular type of contentassociated with the entity named in the query (e.g., Mark's posts,Mark's photos, Mark's videos). The list may further comprise keywordqueries 440, each comprising a stored candidate keyword (e.g., “ai,”“internet.org,” “refugee crisis,” “oculus”) and a reference to theentity associated with the candidate keywords (e.g., “Mark”). Eachsuggested keyword query entry may further comprise a brief descriptionof the source based on which the corresponding keyword is generated(e.g. “Mark posted about this”). The candidate keywords included in thesuggested keyword queries may have been generated based on n-gramsextracted from Mark's posts and either stored in one or more data stores164 or cached on a client system 130 associated with the second entityby the social-networking system 160 ahead of time. The social-networkingsystem 160 may have ranked the candidate keywords based on one or morecriteria and assigned a suggested keyword query comprising ahigher-ranked candidate keyword a higher position on the dropdown menu.The second entity may be able to click on one of the suggested keywordqueries to conduct a search against the online social network with thequery clicked on. Although FIG. 4 illustrates displaying, in aninterface corresponding to a first entity, particular keyword querysuggestions associated with an entity in a particular manner, thisdisclosure contemplates displaying, in an interface corresponding to afirst entity, any suitable keyword query suggestions associated with anentity in any suitable manner.

FIGS. 5A-5B illustrate an example newsfeed interface for displayingkeyword query suggestions. In this example, the newsfeed interface andthe query suggestions correspond to different entities. A second entity,Matthew, may stay on his own newsfeed interface 500 and initiate asearch from this interface by clicking on the query field 510. In afirst scenario as illustrated by FIG. 5A, the second entity may type inthe query field 510 a particular partial query “Mar.” Thesocial-networking system 160, as part of its typehead functionality, mayparse the partial query to identify at least the n-gram “Mar” anddetermine that the identified n-gram corresponds to an entity nodecorresponding to Mark. A dropdown menu 520 comprising a list ofsuggested queries may then be displayed. The list may comprise user andtrending topic queries 530, each comprising a query string and a briefdescription of the query. The list may also comprise keyword queries540, each comprising a candidate keyword (e.g., “ai,” “internet.org”)generated based on a n-gram extracted from posts associated with Markand a reference to Mark (e.g., “Mark”). Note that the current dropdownmenu 520 may only have two slots for displaying suggested queries withcandidate keywords generated based on posts. Therefore, thesocial-networking system 160 may only display suggested keyword queriescomprising the keywords ranked top two among all stored candidatekeywords associated with Mark. The second entity may be able to click onone of the suggested keyword queries to conduct a search against theonline social network with the query clicked on.

In a second scenario as illustrated by FIG. 5B, the second entity,Matthew, may click on the query field 510 associated with the newsfeedinterface 500 without typing in a partial query. The social-networkingsystem 160 may access a search history of the second entity anddetermine that the second entity has recently searched for Mark andXiao. Based on this determination, the social-networking system 160 maysend to a client system 130 of the second entity for display a dropdownmenu 550, which comprises a list of suggested queries. The list maycomprise user queries 560 and 580, and keyword queries 570 and 590. Thekeyword queries 570 and 590 may each comprise a keyword (e.g., “ai,”“internet.org,” “Tesla,” “gravitational waves”) and a reference to theuser associated with the keyword (e.g., “Mark,” “Xiao”). Here, thesuggested queries associated with Mark may be displayed above suggestedqueries associated with Xiao because the second entity may have morerecently searched for Mark than Xiao. The second entity may be able toclick on one of the suggested keyword queries to conduct a searchagainst the online social network with the query clicked on. AlthoughFIGS. 5A-5B illustrate displaying, in an interface unrelated to a firstentity, keyword query suggestions associated with the first entity in aparticular manner, this disclosure contemplates displaying, in aninterface unrelated to a first entity, keyword query suggestionsassociated with the first entity in any suitable manner.

FIG. 6 illustrates an example method 600 for providing customizedkeyword query suggestions related to particular entities of an onlinesocial network. The method may begin at step 610, where thesocial-networking system 160 may access a plurality of posts of anonline social network, each post being associated with a first entity ofthe online social network. At step 620, the social-networking system 160may generate a plurality of candidate keywords by extracting one or moren-grams from content of the accessed posts. At step 630, thesocial-networking system 160 may calculate a rank for each candidatekeyword based at least in part on a number of social signals associatedwith the post from which the n-gram corresponding to the candidatekeyword was extracted. At step 640, the social-networking system 160 maystore one or more candidate keywords in association with the firstentity, each stored candidate keyword having a calculated rank higherthan a threshold rank. At step 650, the social-networking system 160 maysend to a second entity of the online social network one or moresuggested queries associated with the first entity, each suggested querycomprising one or more of the stored candidate keywords associated withthe first entity. Particular embodiments may repeat one or more steps ofthe method of FIG. 6, where appropriate. Although this disclosuredescribes and illustrates particular steps of the method of FIG. 6 asoccurring in a particular order, this disclosure contemplates anysuitable steps of the method of FIG. 6 occurring in any suitable order.Moreover, although this disclosure describes and illustrates an examplemethod for providing customized keyword query suggestions related toparticular entities of an online social network including the particularsteps of the method of FIG. 6, this disclosure contemplates any suitablemethod for providing customized keyword query suggestions related toparticular entities of an online social network including any suitablesteps, which may include all, some, or none of the steps of the methodof FIG. 6, where appropriate. Furthermore, although this disclosuredescribes and illustrates particular components, devices, or systemscarrying out particular steps of the method of FIG. 6, this disclosurecontemplates any suitable combination of any suitable components,devices, or systems carrying out any suitable steps of the method ofFIG. 6.

Social Graph Affinity and Coefficient

In particular embodiments, the social-networking system 160 maydetermine the social-graph affinity (which may be referred to herein as“affinity”) of various social-graph entities for each other. Affinitymay represent the strength of a relationship or level of interestbetween particular objects associated with the online social network,such as users, concepts, content, actions, advertisements, other objectsassociated with the online social network, or any suitable combinationthereof. Affinity may also be determined with respect to objectsassociated with third-party systems 170 or other suitable systems. Anoverall affinity for a social-graph entity for each user, subjectmatter, or type of content may be established. The overall affinity maychange based on continued monitoring of the actions or relationshipsassociated with the social-graph entity. Although this disclosuredescribes determining particular affinities in a particular manner, thisdisclosure contemplates determining any suitable affinities in anysuitable manner.

In particular embodiments, the social-networking system 160 may measureor quantify social-graph affinity using an affinity coefficient (whichmay be referred to herein as “coefficient”). The coefficient mayrepresent or quantify the strength of a relationship between particularobjects associated with the online social network. The coefficient mayalso represent a probability or function that measures a predictedprobability that a user will perform a particular action based on theuser's interest in the action. In this way, a user's future actions maybe predicted based on the user's prior actions, where the coefficientmay be calculated at least in part on the history of the user's actions.Coefficients may be used to predict any number of actions, which may bewithin or outside of the online social network. As an example and not byway of limitation, these actions may include various types ofcommunications, such as sending messages, posting content, or commentingon content; various types of observation actions, such as accessing orviewing profile interfaces, media, or other suitable content; varioustypes of coincidence information about two or more social-graphentities, such as being in the same group, tagged in the samephotograph, checked-in at the same location, or attending the sameevent; or other suitable actions. Although this disclosure describesmeasuring affinity in a particular manner, this disclosure contemplatesmeasuring affinity in any suitable manner.

In particular embodiments, the social-networking system 160 may use avariety of factors to calculate a coefficient. These factors mayinclude, for example, user actions, types of relationships betweenobjects, location information, other suitable factors, or anycombination thereof. In particular embodiments, different factors may beweighted differently when calculating the coefficient. The weights foreach factor may be static or the weights may change according to, forexample, the user, the type of relationship, the type of action, theuser's location, and so forth. Ratings for the factors may be combinedaccording to their weights to determine an overall coefficient for theuser. As an example and not by way of limitation, particular useractions may be assigned both a rating and a weight while a relationshipassociated with the particular user action is assigned a rating and acorrelating weight (e.g., so the weights total 100%). To calculate thecoefficient of a user towards a particular object, the rating assignedto the user's actions may comprise, for example, 60% of the overallcoefficient, while the relationship between the user and the object maycomprise 40% of the overall coefficient. In particular embodiments, thesocial-networking system 160 may consider a variety of variables whendetermining weights for various factors used to calculate a coefficient,such as, for example, the time since information was accessed, decayfactors, frequency of access, relationship to information orrelationship to the object about which information was accessed,relationship to social-graph entities connected to the object, short- orlong-term averages of user actions, user feedback, other suitablevariables, or any combination thereof. As an example and not by way oflimitation, a coefficient may include a decay factor that causes thestrength of the signal provided by particular actions to decay withtime, such that more recent actions are more relevant when calculatingthe coefficient. The ratings and weights may be continuously updatedbased on continued tracking of the actions upon which the coefficient isbased. Any type of process or algorithm may be employed for assigning,combining, averaging, and so forth the ratings for each factor and theweights assigned to the factors. In particular embodiments, thesocial-networking system 160 may determine coefficients usingmachine-learning algorithms trained on historical actions and past userresponses, or data farmed from users by exposing them to various optionsand measuring responses. Although this disclosure describes calculatingcoefficients in a particular manner, this disclosure contemplatescalculating coefficients in any suitable manner.

In particular embodiments, the social-networking system 160 maycalculate a coefficient based on a user's actions. The social-networkingsystem 160 may monitor such actions on the online social network, on athird-party system 170, on other suitable systems, or any combinationthereof. Any suitable type of user actions may be tracked or monitored.Typical user actions include viewing profile interfaces, creating orposting content, interacting with content, tagging or being tagged inimages, joining groups, listing and confirming attendance at events,checking-in at locations, liking particular interfaces, creatinginterfaces, and performing other tasks that facilitate social action. Inparticular embodiments, the social-networking system 160 may calculate acoefficient based on the user's actions with particular types ofcontent. The content may be associated with the online social network, athird-party system 170, or another suitable system. The content mayinclude users, profile interfaces, posts, news stories, headlines,instant messages, chat room conversations, emails, advertisements,pictures, video, music, other suitable objects, or any combinationthereof. The social-networking system 160 may analyze a user's actionsto determine whether one or more of the actions indicate an affinity forsubject matter, content, other users, and so forth. As an example andnot by way of limitation, if a user may make frequently posts contentrelated to “coffee” or variants thereof, the social-networking system160 may determine the user has a high coefficient with respect to theconcept “coffee”. Particular actions or types of actions may be assigneda higher weight and/or rating than other actions, which may affect theoverall calculated coefficient. As an example and not by way oflimitation, if a first user emails a second user, the weight or therating for the action may be higher than if the first user simply viewsthe user-profile interface for the second user.

In particular embodiments, the social-networking system 160 maycalculate a coefficient based on the type of relationship betweenparticular objects. Referencing the social graph 200, thesocial-networking system 160 may analyze the number and/or type of edges206 connecting particular user nodes 202 and concept nodes 204 whencalculating a coefficient. As an example and not by way of limitation,user nodes 202 that are connected by a spouse-type edge (representingthat the two users are married) may be assigned a higher coefficientthan a user nodes 202 that are connected by a friend-type edge. In otherwords, depending upon the weights assigned to the actions andrelationships for the particular user, the overall affinity may bedetermined to be higher for content about the user's spouse than forcontent about the user's friend. In particular embodiments, therelationships a user has with another object may affect the weightsand/or the ratings of the user's actions with respect to calculating thecoefficient for that object. As an example and not by way of limitation,if a user is tagged in first photo, but merely likes a second photo, thesocial-networking system 160 may determine that the user has a highercoefficient with respect to the first photo than the second photobecause having a tagged-in-type relationship with content may beassigned a higher weight and/or rating than having a like-typerelationship with content. In particular embodiments, thesocial-networking system 160 may calculate a coefficient for a firstuser based on the relationship one or more second users have with aparticular object. In other words, the connections and coefficientsother users have with an object may affect the first user's coefficientfor the object. As an example and not by way of limitation, if a firstuser is connected to or has a high coefficient for one or more secondusers, and those second users are connected to or have a highcoefficient for a particular object, the social-networking system 160may determine that the first user should also have a relatively highcoefficient for the particular object. In particular embodiments, thecoefficient may be based on the degree of separation between particularobjects. The lower coefficient may represent the decreasing likelihoodthat the first user will share an interest in content objects of theuser that is indirectly connected to the first user in the social graph200. As an example and not by way of limitation, social-graph entitiesthat are closer in the social graph 200 (i.e., fewer degrees ofseparation) may have a higher coefficient than entities that are furtherapart in the social graph 200.

In particular embodiments, the social-networking system 160 maycalculate a coefficient based on location information. Objects that aregeographically closer to each other may be considered to be more relatedor of more interest to each other than more distant objects. Inparticular embodiments, the coefficient of a user towards a particularobject may be based on the proximity of the object's location to acurrent location associated with the user (or the location of a clientsystem 130 of the user). A first user may be more interested in otherusers or concepts that are closer to the first user. As an example andnot by way of limitation, if a user is one mile from an airport and twomiles from a gas station, the social-networking system 160 may determinethat the user has a higher coefficient for the airport than the gasstation based on the proximity of the airport to the user.

In particular embodiments, the social-networking system 160 may performparticular actions with respect to a user based on coefficientinformation. Coefficients may be used to predict whether a user willperform a particular action based on the user's interest in the action.A coefficient may be used when generating or presenting any type ofobjects to a user, such as advertisements, search results, news stories,media, messages, notifications, or other suitable objects. Thecoefficient may also be utilized to rank and order such objects, asappropriate. In this way, the social-networking system 160 may provideinformation that is relevant to user's interests and currentcircumstances, increasing the likelihood that they will find suchinformation of interest. In particular embodiments, thesocial-networking system 160 may generate content based on coefficientinformation. Content objects may be provided or selected based oncoefficients specific to a user. As an example and not by way oflimitation, the coefficient may be used to generate media for the user,where the user may be presented with media for which the user has a highoverall coefficient with respect to the media object. As another exampleand not by way of limitation, the coefficient may be used to generateadvertisements for the user, where the user may be presented withadvertisements for which the user has a high overall coefficient withrespect to the advertised object. In particular embodiments, thesocial-networking system 160 may generate search results based oncoefficient information. Search results for a particular user may bescored or ranked based on the coefficient associated with the searchresults with respect to the querying user. As an example and not by wayof limitation, search results corresponding to objects with highercoefficients may be ranked higher on a search-results interface thanresults corresponding to objects having lower coefficients.

In particular embodiments, the social-networking system 160 maycalculate a coefficient in response to a request for a coefficient froma particular system or process. To predict the likely actions a user maytake (or may be the subject of) in a given situation, any process mayrequest a calculated coefficient for a user. The request may alsoinclude a set of weights to use for various factors used to calculatethe coefficient. This request may come from a process running on theonline social network, from a third-party system 170 (e.g., via an APIor other communication channel), or from another suitable system. Inresponse to the request, the social-networking system 160 may calculatethe coefficient (or access the coefficient information if it haspreviously been calculated and stored). In particular embodiments, thesocial-networking system 160 may measure an affinity with respect to aparticular process. Different processes (both internal and external tothe online social network) may request a coefficient for a particularobject or set of objects. The social-networking system 160 may provide ameasure of affinity that is relevant to the particular process thatrequested the measure of affinity. In this way, each process receives ameasure of affinity that is tailored for the different context in whichthe process will use the measure of affinity.

In connection with social-graph affinity and affinity coefficients,particular embodiments may utilize one or more systems, components,elements, functions, methods, operations, or steps disclosed in U.S.patent application Ser. No. 11/503,093, filed 11 Aug. 2006, U.S. patentapplication Ser. No. 12/977,027, filed 22 Dec. 2010, U.S. patentapplication Ser. No. 12/978,265, filed 23 Dec. 2010, and U.S. patentapplication Ser. No. 13/632,869, filed 1 Oct. 2012, each of which isincorporated by reference.

Privacy

In particular embodiments, one or more of the content objects of theonline social network may be associated with a privacy setting. Theprivacy settings (or “access settings”) for an object may be stored inany suitable manner, such as, for example, in association with theobject, in an index on an authorization server, in another suitablemanner, or any combination thereof. A privacy setting of an object mayspecify how the object (or particular information associated with anobject) can be accessed (e.g., viewed or shared) using the online socialnetwork. Where the privacy settings for an object allow a particularuser to access that object, the object may be described as being“visible” with respect to that user. As an example and not by way oflimitation, a user of the online social network may specify privacysettings for a user-profile interface that identify a set of users thatmay access the work experience information on the user-profileinterface, thus excluding other users from accessing the information. Inparticular embodiments, the privacy settings may specify a “blockedlist” of users that should not be allowed to access certain informationassociated with the object. In other words, the blocked list may specifyone or more users or entities for which an object is not visible. As anexample and not by way of limitation, a user may specify a set of usersthat may not access photos albums associated with the user, thusexcluding those users from accessing the photo albums (while alsopossibly allowing certain users not within the set of users to accessthe photo albums). In particular embodiments, privacy settings may beassociated with particular social-graph elements. Privacy settings of asocial-graph element, such as a node or an edge, may specify how thesocial-graph element, information associated with the social-graphelement, or content objects associated with the social-graph element canbe accessed using the online social network. As an example and not byway of limitation, a particular concept node 204 corresponding to aparticular photo may have a privacy setting specifying that the photomay only be accessed by users tagged in the photo and their friends. Inparticular embodiments, privacy settings may allow users to opt in oropt out of having their actions logged by the social-networking system160 or shared with other systems (e.g., a third-party system 170). Inparticular embodiments, the privacy settings associated with an objectmay specify any suitable granularity of permitted access or denial ofaccess. As an example and not by way of limitation, access or denial ofaccess may be specified for particular users (e.g., only me, myroommates, and my boss), users within a particular degrees-of-separation(e.g., friends, or friends-of-friends), user groups (e.g., the gamingclub, my family), user networks (e.g., employees of particularemployers, students or alumni of particular university), all users(“public”), no users (“private”), users of third-party systems 170,particular applications (e.g., third-party applications, externalwebsites), other suitable users or entities, or any combination thereof.Although this disclosure describes using particular privacy settings ina particular manner, this disclosure contemplates using any suitableprivacy settings in any suitable manner.

In particular embodiments, one or more servers 162 may beauthorization/privacy servers for enforcing privacy settings. Inresponse to a request from a user (or other entity) for a particularobject stored in a data store 164, the social-networking system 160 maysend a request to the data store 164 for the object. The request mayidentify the user associated with the request and may only be sent tothe user (or a client system 130 of the user) if the authorizationserver determines that the user is authorized to access the object basedon the privacy settings associated with the object. If the requestinguser is not authorized to access the object, the authorization servermay prevent the requested object from being retrieved from the datastore 164, or may prevent the requested object from be sent to the user.In the search query context, an object may only be generated as a searchresult if the querying user is authorized to access the object. In otherwords, the object must have a visibility that is visible to the queryinguser. If the object has a visibility that is not visible to the user,the object may be excluded from the search results. Although thisdisclosure describes enforcing privacy settings in a particular manner,this disclosure contemplates enforcing privacy settings in any suitablemanner.

Systems and Methods

FIG. 7 illustrates an example computer system 700. In particularembodiments, one or more computer systems 700 perform one or more stepsof one or more methods described or illustrated herein. In particularembodiments, one or more computer systems 700 provide functionalitydescribed or illustrated herein. In particular embodiments, softwarerunning on one or more computer systems 700 performs one or more stepsof one or more methods described or illustrated herein or providesfunctionality described or illustrated herein. Particular embodimentsinclude one or more portions of one or more computer systems 700.Herein, reference to a computer system may encompass a computing device,and vice versa, where appropriate. Moreover, reference to a computersystem may encompass one or more computer systems, where appropriate.

This disclosure contemplates any suitable number of computer systems700. This disclosure contemplates computer system 700 taking anysuitable physical form. As example and not by way of limitation,computer system 700 may be an embedded computer system, a system-on-chip(SOC), a single-board computer system (SBC) (such as, for example, acomputer-on-module (COM) or system-on-module (SOM)), a desktop computersystem, a laptop or notebook computer system, an interactive kiosk, amainframe, a mesh of computer systems, a mobile telephone, a personaldigital assistant (PDA), a server, a tablet computer system, or acombination of two or more of these. Where appropriate, computer system700 may include one or more computer systems 700; be unitary ordistributed; span multiple locations; span multiple machines; spanmultiple data centers; or reside in a cloud, which may include one ormore cloud components in one or more networks. Where appropriate, one ormore computer systems 700 may perform without substantial spatial ortemporal limitation one or more steps of one or more methods describedor illustrated herein. As an example and not by way of limitation, oneor more computer systems 700 may perform in real time or in batch modeone or more steps of one or more methods described or illustratedherein. One or more computer systems 700 may perform at different timesor at different locations one or more steps of one or more methodsdescribed or illustrated herein, where appropriate.

In particular embodiments, computer system 700 includes a processor 702,memory 704, storage 706, an input/output (I/O) interface 708, acommunication interface 710, and a bus 712. Although this disclosuredescribes and illustrates a particular computer system having aparticular number of particular components in a particular arrangement,this disclosure contemplates any suitable computer system having anysuitable number of any suitable components in any suitable arrangement.

In particular embodiments, processor 702 includes hardware for executinginstructions, such as those making up a computer program. As an exampleand not by way of limitation, to execute instructions, processor 702 mayretrieve (or fetch) the instructions from an internal register, aninternal cache, memory 704, or storage 706; decode and execute them; andthen write one or more results to an internal register, an internalcache, memory 704, or storage 706. In particular embodiments, processor702 may include one or more internal caches for data, instructions, oraddresses. This disclosure contemplates processor 702 including anysuitable number of any suitable internal caches, where appropriate. Asan example and not by way of limitation, processor 702 may include oneor more instruction caches, one or more data caches, and one or moretranslation lookaside buffers (TLBs). Instructions in the instructioncaches may be copies of instructions in memory 704 or storage 706, andthe instruction caches may speed up retrieval of those instructions byprocessor 702. Data in the data caches may be copies of data in memory704 or storage 706 for instructions executing at processor 702 tooperate on; the results of previous instructions executed at processor702 for access by subsequent instructions executing at processor 702 orfor writing to memory 704 or storage 706; or other suitable data. Thedata caches may speed up read or write operations by processor 702. TheTLBs may speed up virtual-address translation for processor 702. Inparticular embodiments, processor 702 may include one or more internalregisters for data, instructions, or addresses. This disclosurecontemplates processor 702 including any suitable number of any suitableinternal registers, where appropriate. Where appropriate, processor 702may include one or more arithmetic logic units (ALUs); be a multi-coreprocessor; or include one or more processors 702. Although thisdisclosure describes and illustrates a particular processor, thisdisclosure contemplates any suitable processor.

In particular embodiments, memory 704 includes main memory for storinginstructions for processor 702 to execute or data for processor 702 tooperate on. As an example and not by way of limitation, computer system700 may load instructions from storage 706 or another source (such as,for example, another computer system 700) to memory 704. Processor 702may then load the instructions from memory 704 to an internal registeror internal cache. To execute the instructions, processor 702 mayretrieve the instructions from the internal register or internal cacheand decode them. During or after execution of the instructions,processor 702 may write one or more results (which may be intermediateor final results) to the internal register or internal cache. Processor702 may then write one or more of those results to memory 704. Inparticular embodiments, processor 702 executes only instructions in oneor more internal registers or internal caches or in memory 704 (asopposed to storage 706 or elsewhere) and operates only on data in one ormore internal registers or internal caches or in memory 704 (as opposedto storage 706 or elsewhere). One or more memory buses (which may eachinclude an address bus and a data bus) may couple processor 702 tomemory 704. Bus 712 may include one or more memory buses, as describedbelow. In particular embodiments, one or more memory management units(MMUs) reside between processor 702 and memory 704 and facilitateaccesses to memory 704 requested by processor 702. In particularembodiments, memory 704 includes random access memory (RAM). This RAMmay be volatile memory, where appropriate Where appropriate, this RAMmay be dynamic RAM (DRAM) or static RAM (SRAM). Moreover, whereappropriate, this RAM may be single-ported or multi-ported RAM. Thisdisclosure contemplates any suitable RAM. Memory 704 may include one ormore memories 704, where appropriate. Although this disclosure describesand illustrates particular memory, this disclosure contemplates anysuitable memory.

In particular embodiments, storage 706 includes mass storage for data orinstructions. As an example and not by way of limitation, storage 706may include a hard disk drive (HDD), a floppy disk drive, flash memory,an optical disc, a magneto-optical disc, magnetic tape, or a UniversalSerial Bus (USB) drive or a combination of two or more of these. Storage706 may include removable or non-removable (or fixed) media, whereappropriate. Storage 706 may be internal or external to computer system700, where appropriate. In particular embodiments, storage 706 isnon-volatile, solid-state memory. In particular embodiments, storage 706includes read-only memory (ROM). Where appropriate, this ROM may bemask-programmed ROM, programmable ROM (PROM), erasable PROM (EPROM),electrically erasable PROM (EEPROM), electrically alterable ROM (EAROM),or flash memory or a combination of two or more of these. Thisdisclosure contemplates mass storage 706 taking any suitable physicalform. Storage 706 may include one or more storage control unitsfacilitating communication between processor 702 and storage 706, whereappropriate. Where appropriate, storage 706 may include one or morestorages 706. Although this disclosure describes and illustratesparticular storage, this disclosure contemplates any suitable storage.

In particular embodiments, I/O interface 708 includes hardware,software, or both, providing one or more interfaces for communicationbetween computer system 700 and one or more I/O devices. Computer system700 may include one or more of these I/O devices, where appropriate. Oneor more of these I/O devices may enable communication between a personand computer system 700. As an example and not by way of limitation, anI/O device may include a keyboard, keypad, microphone, monitor, mouse,printer, scanner, speaker, still camera, stylus, tablet, touch screen,trackball, video camera, another suitable I/O device or a combination oftwo or more of these. An I/O device may include one or more sensors.This disclosure contemplates any suitable I/O devices and any suitableI/O interfaces 708 for them. Where appropriate, I/O interface 708 mayinclude one or more device or software drivers enabling processor 702 todrive one or more of these I/O devices. I/O interface 708 may includeone or more I/O interfaces 708, where appropriate. Although thisdisclosure describes and illustrates a particular I/O interface, thisdisclosure contemplates any suitable I/O interface.

In particular embodiments, communication interface 710 includeshardware, software, or both providing one or more interfaces forcommunication (such as, for example, packet-based communication) betweencomputer system 700 and one or more other computer systems 700 or one ormore networks. As an example and not by way of limitation, communicationinterface 710 may include a network interface controller (NIC) ornetwork adapter for communicating with an Ethernet or other wire-basednetwork or a wireless NIC (WNIC) or wireless adapter for communicatingwith a wireless network, such as a WI-FI network. This disclosurecontemplates any suitable network and any suitable communicationinterface 710 for it. As an example and not by way of limitation,computer system 700 may communicate with an ad hoc network, a personalarea network (PAN), a local area network (LAN), a wide area network(WAN), a metropolitan area network (MAN), or one or more portions of theInternet or a combination of two or more of these. One or more portionsof one or more of these networks may be wired or wireless. As anexample, computer system 700 may communicate with a wireless PAN (WPAN)(such as, for example, a BLUETOOTH WPAN), a WI-FI network, a WI-MAXnetwork, a cellular telephone network (such as, for example, a GlobalSystem for Mobile Communications (GSM) network), or other suitablewireless network or a combination of two or more of these. Computersystem 700 may include any suitable communication interface 710 for anyof these networks, where appropriate. Communication interface 710 mayinclude one or more communication interfaces 710, where appropriate.Although this disclosure describes and illustrates a particularcommunication interface, this disclosure contemplates any suitablecommunication interface.

In particular embodiments, bus 712 includes hardware, software, or bothcoupling components of computer system 700 to each other. As an exampleand not by way of limitation, bus 712 may include an AcceleratedGraphics Port (AGP) or other graphics bus, an Enhanced Industry StandardArchitecture (EISA) bus, a front-side bus (FSB), a HYPERTRANSPORT (HT)interconnect, an Industry Standard Architecture (ISA) bus, an INFINIBANDinterconnect, a low-pin-count (LPC) bus, a memory bus, a Micro ChannelArchitecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, aPCI-Express (PCIe) bus, a serial advanced technology attachment (SATA)bus, a Video Electronics Standards Association local (VLB) bus, oranother suitable bus or a combination of two or more of these. Bus 712may include one or more buses 712, where appropriate. Although thisdisclosure describes and illustrates a particular bus, this disclosurecontemplates any suitable bus or interconnect.

Herein, a computer-readable non-transitory storage medium or media mayinclude one or more semiconductor-based or other integrated circuits(ICs) (such, as for example, field-programmable gate arrays (FPGAs) orapplication-specific ICs (ASICs)), hard disk drives (HDDs), hybrid harddrives (HHDs), optical discs, optical disc drives (ODDs),magneto-optical discs, magneto-optical drives, floppy diskettes, floppydisk drives (FDDs), magnetic tapes, solid-state drives (SSDs),RAM-drives, SECURE DIGITAL cards or drives, any other suitablecomputer-readable non-transitory storage media, or any suitablecombination of two or more of these, where appropriate. Acomputer-readable non-transitory storage medium may be volatile,non-volatile, or a combination of volatile and non-volatile, whereappropriate.

Miscellaneous

Herein, “or” is inclusive and not exclusive, unless expressly indicatedotherwise or indicated otherwise by context. Therefore, herein, “A or B”means “A, B, or both,” unless expressly indicated otherwise or indicatedotherwise by context. Moreover, “and” is both joint and several, unlessexpressly indicated otherwise or indicated otherwise by context.Therefore, herein, “A and B” means “A and B, jointly or severally,”unless expressly indicated otherwise or indicated otherwise by context.

The scope of this disclosure encompasses all changes, substitutions,variations, alterations, and modifications to the example embodimentsdescribed or illustrated herein that a person having ordinary skill inthe art would comprehend. The scope of this disclosure is not limited tothe example embodiments described or illustrated herein. Moreover,although this disclosure describes and illustrates respectiveembodiments herein as including particular components, elements,feature, functions, operations, or steps, any of these embodiments mayinclude any combination or permutation of any of the components,elements, features, functions, operations, or steps described orillustrated anywhere herein that a person having ordinary skill in theart would comprehend. Furthermore, reference in the appended claims toan apparatus or system or a component of an apparatus or system beingadapted to, arranged to, capable of, configured to, enabled to, operableto, or operative to perform a particular function encompasses thatapparatus, system, component, whether or not it or that particularfunction is activated, turned on, or unlocked, as long as thatapparatus, system, or component is so adapted, arranged, capable,configured, enabled, operable, or operative. Additionally, although thisdisclosure describes or illustrates particular embodiments as providingparticular advantages, particular embodiments may provide none, some, orall of these advantages.

What is claimed is:
 1. A method comprising, by one or more computingdevices: accessing a plurality of posts authored by a plurality ofentities of an online social network, each post being associated with afirst entity of the online social network; generating a plurality ofcandidate keywords associated with the first entity by extracting one ormore n-grams from content of the posts associated with the first entity;calculating a rank for each candidate keyword based at least in part ona number of social signals associated with the post from which then-gram corresponding to the candidate keyword was extracted; storing oneor more candidate keywords in association with the first entity, eachstored candidate keyword having a calculated rank higher than athreshold rank; and sending, to a client system of a second entity ofthe online social network in response to determining that the secondentity is currently interacting with an interface of the online socialnetwork associated with the first entity, one or more suggested queriesassociated with the first entity for display on the client system, eachsuggested query comprising one or more of the stored candidate keywordsassociated with the first entity.
 2. The method of claim 1, furthercomprising: accessing a social graph comprising a plurality of nodes anda plurality of edges connecting the nodes, each of the edges between twoof the nodes representing a single degree of separation between them,the nodes comprising: a plurality of entity nodes corresponding to aplurality of entities associated with the online social network,respectively, wherein the first entity corresponds to a first entitynode of the plurality of entity nodes, and wherein the second entitycorresponds to a second entity node of the plurality of entity nodes;and a plurality of content nodes corresponding to a plurality of postsof the online social network, respectively, each content node beingconnected to one or more of the entity nodes by one or more edges. 3.The method of claim 2, further comprising determining that the secondentity is currently accessing, via the client system, an interface ofthe online social network associated with the first entity node.
 4. Themethod of claim 2, further comprising accessing a search historyassociated with the second entity, the search history comprising aplurality of queries, wherein at least one of the queries of the searchhistory is associated with the first entity node.
 5. The method of claim2, further comprising: receiving, from the client system of the secondentity, an unstructured text query; parsing the text query to identifyone or more n-grams; and determining that at least one of the identifiedn-grams corresponds to the first entity node.
 6. The method of claim 1,wherein the accessed posts comprise posts generated within a specifiedtimeframe.
 7. The method of claim 1, wherein a number of posts accessedis the smaller of: a specified number of posts; or a total number ofposts associated with the first entity of the online social network. 8.The method of claim 1, wherein generating the plurality of candidatekeywords comprises: extracting one or more n-grams from the content ofthe accessed posts; calculating a relevance score for each extractedn-gram; and generating a candidate keyword corresponding to each n-gramhaving a calculated relevance score greater than a threshold relevancescore.
 9. The method of claim 1, wherein generating the plurality ofcandidate keywords further comprises: accessing one or more imagesassociated with each of one or more of the accessed posts; identifyingone or more n-grams corresponding to one or more features of eachaccessed image; and generating a candidate keyword for each of one ormore of the identified n-grams.
 10. The method of claim 1, wherein thesocial signals associated with each post comprise one or more of: anaccessing or viewing of the post; a comment on the post; a sharing ofthe post; or a liking of the post, the comment on the post, or thesharing of the post.
 11. The method of claim 1, wherein calculating therank for each candidate keyword is further based on analysis of thecandidate keyword according to a language model.
 12. The method of claim1, wherein calculating the rank for each candidate keyword is furtherbased on a time of creation associated with the post from which then-gram corresponding to the candidate keyword was extracted.
 13. Themethod of claim 1, wherein calculating the rank for each candidatekeyword comprises: determining that a first candidate keyword appears ina list of trending-topic keywords; and up-ranking the first candidatekeyword based on the determination.
 14. The method of claim 1, whereincalculating the rank for each candidate keyword comprises: determiningthat a first candidate keyword appears in more than one accessed postsassociated with the first entity of the online social network;calculating a number of accessed posts comprising the first candidatekeyword; and up-ranking the first candidate keyword based on thecalculated number of accessed posts.
 15. The method of claim 1, whereincalculating the rank for each candidate keyword comprises, for a firstcandidate keyword: determining that one or more n-grams corresponding toa particular number of second candidate keywords, respectively, wereextracted from the post from which the n-gram corresponding to the firstcandidate keyword was extracted; determining that the particular numberof second candidate keywords each has a higher rank than the firstcandidate keyword; and down-ranking the first candidate keyword based onthe determinations.
 16. The method of claim 1, wherein each accessedpost is associated with a privacy setting defining a visibility of thepost that is visible to at least the second entity.
 17. The method ofclaim 1, wherein storing the one or more candidate keywords inassociation with the first entity comprises storing the candidatekeywords in one or more data stores associated with the online socialnetwork.
 18. The method of claim 1, wherein storing the one or morecandidate keywords in association with the first entity comprisesstoring the candidate keywords on a local cache of the client system ofthe second entity.
 19. One or more computer-readable non-transitorystorage media embodying software that is operable when executed to:access a plurality of posts authored by a plurality of entities of anonline social network, each post being associated with a first entity ofthe online social network; generate a plurality of candidate keywordsassociated with the first entity by extracting one or more n-grams fromcontent of the posts associated with the first entity; calculate a rankfor each candidate keyword based at least in part on a number of socialsignals associated with the post from which the n-gram corresponding tothe candidate keyword was extracted; store one or more candidatekeywords in association with the first entity, each stored candidatekeyword having a calculated rank higher than a threshold rank; and send,to a client system of a second entity of the online social network inresponse to determining that the second entity is currently interactingwith an interface of the online social network associated with the firstentity, one or more suggested queries associated with the first entityfor display on the client system, each suggested query comprising one ormore of the stored candidate keywords associated with the first entity.20. A system comprising: one or more processors; and a non-transitorymemory coupled to the processors comprising instructions executable bythe processors, the processors operable when executing the instructionsto: access a plurality of posts authored by a plurality of entities ofan online social network, each post being associated with a first entityof the online social network; generate a plurality of candidate keywordsassociated with the first entity by extracting one or more n-grams fromcontent of the posts associated with the first entity; calculate a rankfor each candidate keyword based at least in part on a number of socialsignals associated with the post from which the n-gram corresponding tothe candidate keyword was extracted; store one or more candidatekeywords in association with the first entity, each stored candidatekeyword having a calculated rank higher than a threshold rank; and send,to a client system of a second entity of the online social network inresponse to determining that the second entity is currently interactingwith an interface of the online social network associated with the firstentity, one or more suggested queries associated with the first entityfor display on the client system, each suggested query comprising one ormore of the stored candidate keywords associated with the first entity.